Motherboard grounding questions

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Re: Motherboard grounding questions

Postby Twisty » Wed Jun 01, 2016 7:50 pm

Not quite sure how you've got things set up right now, photos would be nice :)

Ideally you want an air gap on the underside of the board but you will probably be fine attaching with velcro providing bit of the board don't short out onto metal, stuff touching plastic pad should be fine, as long as the board isn't moving around and something sharp on the underside of the board scratches though it and contacts the metal underneath.

You say you loosened screws to stop the board from warping - if this is heatsink screws then that could be bad - you don't want to risk the heatsink not being in proper contact with the CPU - if motherboard screws then you can get away with it (esp if doubled up with velcro) but I'd recommend using some washers (nylon,metal, whatever as long as it fits within circle denoting the masking area) underneath so you can both tighten the screws and get a little bit of clearance underneath the board.

No back panel - it's just untidy and may allow dust to settle over time, in theory you might have EMI problem but in practice i've never known this to be a problem. The way I see it making a nice back panel is part of 'tidying up' of the project after it is operational (usually spend several months doing tidying up :)

In terms of ventilation etc would be curious to see a basic sketch of layout then might have some useful feedback. I see dimensions of depths (case height, cpu cooler height) as likely to be critical. I do still suggest that cutting a square in the case directly above cpu cooler and filling it with a fan grill so the cpu fan is sucking in cool air will be very helpful for overall temperatures, e.g. a bit like this https://www.amazon.com/120mm-Black-Steel-Computer-Filter/dp/B00DBW8QZ0?ie=UTF8&*Version*=1&*entries*=0 in the past I've found filters that have a tight metal weave so they also filter out most of the dust. If you have height problems, you could cut a hole for the CPU cooler to poke through and just attach a fan grill directly onto the top of your CPU fan 8) It's going to be untidy if you are not really precice with your measurements and cutting though.
PSU is the other big heat creator, probably a good idea to make sure it is ejecting it's heat directly outside of the case.

Dust is a minor/moderate ongoing maintenance concern, a bit of dust won't kill the PC but it building up over time will cause temps to rise a bit. When it does accumulate I just suck it out with a powerful vacuum which has never caused me a problem although people to take the warnings literally will get worried over the static that a vacuum could potentially create...
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Re: Motherboard grounding questions

Postby LakaWaka » Fri Jun 03, 2016 6:48 pm

Karlsweldt wrote:Ambient temperatures are important with equipment cooling. Could be two or three degrees more for each degree of ambient temperature that the equipment has to disperse. And dryer air is more acceptable to absorbing waste heat than humid air.
As to thermal limits of any CPU, follow the manufacturer's spec sheet. At least 5°C lower than the design maximum for thermal throttling or alarm is recommended.. could be more with some equipment.
Any computing device, radio, TV or similar emits RF and EMF on a broad spectrum. Shielding limits this radiation, and a grounding path may be needed to be effective.. be it Earth ground or electrical ground.

Velcro and all other fabrics are considered non-conductive.. when dry! But if wetted, could be conductive. Depends on the mineral content of the liquid.

Any structure that is susceptible to static build-up should have a slightly resistive grounding path to keep the charge build-up minimal.
Some structures do have a conductive coating or additive that disperses charge build-up to other parts, keeping charge differential to a minimum.. and avoiding spark discharges. Dispersing static charges is critical with circuits and chips that cannot tolerate voltages over 10 volts, or they instantly die.
We all are (or should be) familiar with being about to touch a doorknob or other metal device, and get a spark of maybe 1/4 inch or more that shocks us! Could be more than 10,000 volts in that spark.. but very little current.

When circuit boards are manufactured, the process is almost totally automated. Very little human intervention. Component leads are pre-cut for needed design, but after assembly the board passes over a 'trimmer' that ensures no leads are longer than desired. Should not be more than 1/8 inch. For normal builds, no need to trim those leads. But for specific applications, the need of no exposed leads may be important.. such as surface mounting with an insulating sheet.
Open a PSU, and there is a semi-clear plastic insulator under the circuit board and on the sides to prevent unwanted contacts.
That coating on motherboards and other circuit boards is intended to protect the traces from corrosion, as copper exposed to air wants to revert to its primal stage.. an oxide state. Usually a greenish color. But the coating also protects circuits from accidental contact with foreign objects that could cause shorts.
SSD and SIM cards do have limits on heat. Or they may literally fry internally. They need air circulation to stay 'healthy'.



Gotcha, I'll try to keep the air as cool as possible.

Gotcha, I forgot about the shielding from other stuff, is there any other way to shield besides the ones provided? Mine feels super cheap.

Interesting on the static thing. One thing to mention that when I was building this to take pictures I was on carpet, with the case on carpet, and was touching my live case (this one I'm typing on) to discharge, as I've heard that's how to get rid of static, and I think I might have felt a couple of tiny shocks when touching my PSU. I would assume the PSU 's caps would be able to handle any static, but I did try to be saferf, but I guess I should get one of those wrist bands.


Crazy that there is so much voltage in that spark..... So even if a component dies, it might not affect the computer fully, and you might not notice it, or it might be somethign that isn't really noticable?


I think I see the insulator on the Seasonic unit I got for this one.



I'm still not sure if I should just try to start it up, and see how it goes.. or what.

I could also get standoffs as tall as the Screws, to fully secure the unit, but I am a bit lazy to buy a drill bit and drill the holes, but will if I absolutely have to :).


Thanks for all of the info on this stuff, so much to understand about it.





[quote]Not quite sure how you've got things set up right now, photos would be nice :)

Ideally you want an air gap on the underside of the board but you will probably be fine attaching with velcro providing bit of the board don't short out onto metal, stuff touching plastic pad should be fine, as long as the board isn't moving around and something sharp on the underside of the board scratches though it and contacts the metal underneath.

You say you loosened screws to stop the board from warping - if this is heatsink screws then that could be bad - you don't want to risk the heatsink not being in proper contact with the CPU - if motherboard screws then you can get away with it (esp if doubled up with velcro) but I'd recommend using some washers (nylon,metal, whatever as long as it fits within circle denoting the masking area) underneath so you can both tighten the screws and get a little bit of clearance underneath the board.

No back panel - it's just untidy and may allow dust to settle over time, in theory you might have EMI problem but in practice i've never known this to be a problem. The way I see it making a nice back panel is part of 'tidying up' of the project after it is operational (usually spend several months doing tidying up :)

In terms of ventilation etc would be curious to see a basic sketch of layout then might have some useful feedback. I see dimensions of depths (case height, cpu cooler height) as likely to be critical. I do still suggest that cutting a square in the case directly above cpu cooler and filling it with a fan grill so the cpu fan is sucking in cool air will be very helpful for overall temperatures, e.g. a bit like this https://www.amazon.com/120mm-Black-Stee ... entries*=0 in the past I've found filters that have a tight metal weave so they also filter out most of the dust. If you have height problems, you could cut a hole for the CPU cooler to poke through and just attach a fan grill directly onto the top of your CPU fan 8) It's going to be untidy if you are not really precice with your measurements and cutting though.
PSU is the other big heat creator, probably a good idea to make sure it is ejecting it's heat directly outside of the case.

Dust is a minor/moderate ongoing maintenance concern, a bit of dust won't kill the PC but it building up over time will cause temps to rise a bit. When it does accumulate I just suck it out with a powerful vacuum which has never caused me a problem although people to take the warnings literally will get worried over the static that a vacuum could potentially create...[]/quote]


I tried taking photos of everything. From the pieces of the case itself, to the components in the case, to the cover on, gap between fan and top, etc.

I did noticed that it's gointg to be a PITA to get the wires to fit nicely for the Mobo 24-pin ... I migfht just test it with the seasonic, get some ratings, and then go buy the pic psu I was going to buy,, as that will fit this case so much better than this gigantor seasonic (so glad I got the smaller one hahah).

As shown in one of the pictures what the size looks like between the screw and the leads, as well as teh bottom of the mobo. I didn't get a picture of it on the case, but realized to take one of the bottom as I was packing up.

I figured the Velcro should do well, but I might just get standoffs the size of the screws and secure it that way, as well as velcro to stop any random shorting from the heat sink screws.

Yeah, I loosened the screws a little bit as to still be secured to the mobo, but not have it bend. I would like it to be as snug as possible. I don't need the gap to be larger, I just don't want it to be flexing like crazy, but not sure how bad it is, but seems that it could break stuff.

Speaking of breaing stuff, I was putting the standoffs on the other side and using them to hold the mobo up (before I realized they were too short), and one slipped under the mobo, and not sure if it contacted anything and could have damaged it? Prob nothing but wanted to make sure.

I wanted to get some nicely carved/drilled wooden back panel in some fancy wood. I figured that would work... right?

I just figured that cutting a hole, or even drilling holes, would be super ugly. In the pictures you can see the creative logo was stamped in it seems, as the metal is warped in that spot. I figured I could some how cut those letters out (not sure what kind of tool I would use), and then cover it in some mesh or something.

Yeah, the cutting is a big issue.

I see.. The PSU has a side vent, as well as a top vent. It fits a bit better with the vent facing down, but I really would not want that... This is why more and more the Pico sounds like a much bedtter idea.

I've heard of static from a vacuum, but I've been looking at something called the "Datavac" which is basically a "blower" which blows air and looks like it does an amazing jobl. The regular one is 60$, and the ESD one is about 100$. Sucks the elctrostatic dischange one is so much more, but it seems to be a smart invbestment if you're working around electtronics.

Overall, I probably should have set this up sooner, as I might have returned the seasonic, byut I think it will be okay for now, and I think the cables wont get too much in the way (they kind of are a PITA).

They are bound together, so if I unbind everything it will probably be easier to fit everything where it needs to be...










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I hope you guys like the pictures and such :).
Last edited by LakaWaka on Wed Sep 07, 2016 1:14 am, edited 1 time in total.
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Re: Motherboard grounding questions

Postby Karlsweldt » Sat Jun 04, 2016 5:49 am

With any electronic device, or any other device, tool or component, there are base rules of ensuring proper operation and use, and safety to the user. Those so-called "fine print" rules. Especially toward shielding of unwanted RF signals or EMF fields. Static charge prevention. Grounding of equipment.
Plastics, wool, animal fur and silk all can build a high static charge in low humidity conditions. Yes, the voltage is high.. could be as low as 5,000 volts, or above 200,000 volts. But very little current.. normally less than 100 ma. You get a shock, yes, but 99.9% survival rate. Conductive wrist straps connected to a ground point do bleed off static charges before they become significant. And keeping all components at an even state of charge is a prime rule.
Your thought about repeatedly touching a case that is connected to a grounded outlet is good. But caution of not touching something that has line or high voltage with the other hand must be foremost in mind!

Loose screws usually work out of their place, and wander to live circuits.. maybe under the motherboard, and can cause shorts. If the system is not powered, not much chance of damage.. as there is only the BIOS battery on-board, but if the PSU is powered, but not active, there is a +5 volt 5a source coming into the board!
If a bit of extra clearance is needed, there are red fiber washers that can be used between the board and the standoffs.
As to use of a 20-pin ATX power plug instead of the 24-pin, there may be excess current on some leads, which may cause the solder joint to weaken. There are special adapters for 20- and 24-pin ATX power connections that have the wires exit at a right angle instead of straight. But not easy to find.
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Re: Motherboard grounding questions

Postby Twisty » Fri Jun 17, 2016 1:19 am

It's looking pretty good :D

Looks like you can get the motherboard to sit a bit lower by using different screws on the underside of the heatsink or chopping down the existing ones, It shouldn't be hard to find screws with the same thread in a general hardware store (usually they are M4 thread).

If you decide to go down the standoffs route.
If you've got the coarse threaded standoffs that are designed to be screwed straight into panels then what I've done before is made my own threading tool by hacksawing a small slot across the threads in one of the standoffs - then by carefully pushing and turning this standoff into a pilot hole in the panel the hole I was able to create the thread.
It'd be easier to use a standoff with a fine thread and attach with a nut underneath though ;)

As you've got the side fans you may be able to get away without doing this but I'd still be keen to get an opening above the CPU fan for it to draw air in through, could either drill many small holes or cut an opening and fill it a fan grille or metal mesh.

I would be inclined to tidy up the wiring by opening up the PSU, desoldering the wires from the PCB and shortening/removing wires as required HOWEVER I have to caveat this by saying that this is not something an unqualified person is supposed to do, doing the wrong thing inside a PSU can create fires.
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Re: Motherboard grounding questions

Postby LakaWaka » Tue Jul 26, 2016 8:05 am

Karlsweldt wrote:With any electronic device, or any other device, tool or component, there are base rules of ensuring proper operation and use, and safety to the user. Those so-called "fine print" rules. Especially toward shielding of unwanted RF signals or EMF fields. Static charge prevention. Grounding of equipment.
Plastics, wool, animal fur and silk all can build a high static charge in low humidity conditions. Yes, the voltage is high.. could be as low as 5,000 volts, or above 200,000 volts. But very little current.. normally less than 100 ma. You get a shock, yes, but 99.9% survival rate. Conductive wrist straps connected to a ground point do bleed off static charges before they become significant. And keeping all components at an even state of charge is a prime rule.
Your thought about repeatedly touching a case that is connected to a grounded outlet is good. But caution of not touching something that has line or high voltage with the other hand must be foremost in mind!

Loose screws usually work out of their place, and wander to live circuits.. maybe under the motherboard, and can cause shorts. If the system is not powered, not much chance of damage.. as there is only the BIOS battery on-board, but if the PSU is powered, but not active, there is a +5 volt 5a source coming into the board!
If a bit of extra clearance is needed, there are red fiber washers that can be used between the board and the standoffs.
As to use of a 20-pin ATX power plug instead of the 24-pin, there may be excess current on some leads, which may cause the solder joint to weaken. There are special adapters for 20- and 24-pin ATX power connections that have the wires exit at a right angle instead of straight. But not easy to find.


Sorry I haven't gotten back to you, but thanks for the replies.

So I should keep all that stuff away from my electronics so that it doesn't cause any static.

I bought some nylon to use as a dust filter on my front intake fans, but I'm thinking that might cause static, would you agree? The issue now is that I have the front of my tower basically open, and it's getting dusty. How bad is dust overall? I'm thinking about getting a "Datavac" blower, but people have mentioned dust could get stuck in tiny spots, including in the electronics. I'm curious what you think about this?


-------------------------------------

So for the screws would it be best to keep them snug tight, even though the board bends decently?


I don't think I mentioned anything about a 20 pin connector, I was just saying this one wasn't working well in terms of height, but I need to check out the Pico's size, but it should be okay.


So overall, what do you think I should do for this custom machine?


I'm thinking of just getting some taller standoffs that would be the size of the screws, or a mm taller, and call it a day.

I don't know if a wooden block would work well as a shield for the I/O and all them nasty emissions, or what you would recommend? I want it to also be for the PSU since the I/O takes up half of the unit.


The PSU I'm using currently wont do, so I definitely am going to check out the pico which is found here http://www.mini-box.com/picoPSU-160-XT


I think this will work, but I might have to get another top, or bend the top, since the ram is a bit tall. I will have to take off the heat sink most likely to get it to work as intended though.


Will update :)

Thanks for the help.
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Re: Motherboard grounding questions

Postby Karlsweldt » Tue Jul 26, 2016 5:04 pm

Dust build-up in electronic equipment is not good. Restricts air flow, and insulates components, reducing heat radiation.
There are many types of air-cell filter types, from less than 1/4" thick to over an inch thick. Air flow is not reduced much, but dust particles are trapped in the filter. You might want to try those "scrubbie" pads for dishes. Similar material, and don't restrict air flow too much. Cheap, too. Nylon webbing or stocking would be a decent air filter, but the microscopic particles would still pass through.

If you have an AM radio, tune it to mid-band and bring near any computer. It will start to wail like several sirens. This is RF noise, unwanted. If you cannot find the proper I/O shield for the ports, make one of poster paper to fit. Then wrap aluminum foil on the inside, fold edges to the outer face, poke the holes, and mount in place. The ports should keep it there. Just ensure that no foil gets into any port openings! A "Rube Goldberg" way, but if the part cannot be found, make your own.

Any blower, even a "Datavac" blower, must not be too close to the items being dusted off. Minimal 1 ft. is typical. Same with those "canned air" cleaners. Too powerful an air stream, could dislodge sensitive components. Small fans should not be spun with compressed air, or they may shatter. Best is a soft bristle brush, like a makeup brush or lens brush. Then gently blow dust away. CPU heat sinks get clogged where air enters. Blowing in reverse to a CPU heat sink should clear almost all debris.

That Pico PSU may be ideal for mobile needs, but requires a large amount of 12 volt DC current.. more than 15 amps. And does that Pico PSU provide all the required voltages for a motherboard?

You might be able to find special low height memory modules, may be a bit expensive. But removing the heat sink on standard ones may cause them to run too hot and be damaged.

Not trying to pick your project apart, but some standard rules and proper design would make it something to be proud of.
Good luck with it.
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Re: Motherboard grounding questions

Postby LakaWaka » Tue Jul 26, 2016 5:47 pm

Karlsweldt wrote:Dust build-up in electronic equipment is not good. Restricts air flow, and insulates components, reducing heat radiation.
There are many types of air-cell filter types, from less than 1/4" thick to over an inch thick. Air flow is not reduced much, but dust particles are trapped in the filter. You might want to try those "scrubbie" pads for dishes. Similar material, and don't restrict air flow too much. Cheap, too. Nylon webbing or stocking would be a decent air filter, but the microscopic particles would still pass through.


Hmm, so I should probably get something up and restrict the dust buildup at least a little. So Nylon wont cause any static buildup or anything being directly in front of the fans? I wasn't sure if the nylon got charged if the fan could blow electronics off of the nylon, into the computer.

So Nylon wouldn't work as good as something like a mesh filter?

I'll show you my setup, but it's custom, so the best looking and best able to fit would be a nylon or some other material that I could form.


If you have an AM radio, tune it to mid-band and bring near any computer. It will start to wail like several sirens. This is RF noise, unwanted. If you cannot find the proper I/O shield for the ports, make one of poster paper to fit. Then wrap aluminum foil on the inside, fold edges to the outer face, poke the holes, and mount in place. The ports should keep it there. Just ensure that no foil gets into any port openings! A "Rube Goldberg" way, but if the part cannot be found, make your own.



Is there some sort of test with this radio that would show if we weren't shielded properly, or would it damage components?

Would a wooden back panel work/ I have a shield that came with it, but figured the entire backplate needed to be shield, or only the I/O section?


The wooden panel would be something custom and nice to make everything look better, but not sure how hard it would be to do that. Maybe I could just use the i/o shield that came with it, but worried it might not be enough.

Any blower, even a "Datavac" blower, must not be too close to the items being dusted off. Minimal 1 ft. is typical. Same with those "canned air" cleaners. Too powerful an air stream, could dislodge sensitive components. Small fans should not be spun with compressed air, or they may shatter. Best is a soft bristle brush, like a makeup brush or lens brush. Then gently blow dust away. CPU heat sinks get clogged where air enters. Blowing in reverse to a CPU heat sink should clear almost all debris.


So being too close could be an issue, for breaking things, but what about dust getting stuck in components?

Would you recommend a blower, since I dislike canned air, or is there another method you prefer?


That Pico PSU may be ideal for mobile needs, but requires a large amount of 12 volt DC current.. more than 15 amps. And does that Pico PSU provide all the required voltages for a motherboard?


There is a 192W external laptop type power adapter taht they provide, I believe it's 15 amps, at 192w, but not too sure...

It should provide enough for everything, you could check out the link and see what the specs are, as that would probably make more sense to you.
You might be able to find special low height memory modules, may be a bit expensive. But removing the heat sink on standard ones may cause them to run too hot and be damaged.


Makes sense, it's just a shame that this heat sink fan, and the ram heat sink are so tall. I was thinking of replacing the 1 CPU fan, with thinner, smaller fans but not sure how they would work, and if they would be enough for my Sandy processor.

I figured it would run too hot, so it's best to keep the on.

Not trying to pick your project apart, but some standard rules and proper design would make it something to be proud of.
Good luck with it.



Not at all, I appreciate the feedback, which is why I'm here. Thanks a lot for your time with all of this. I feel I have to re-read a lot of your comments here, but there's a lot of good info.


It's just hard because there isn't really enough room, and my choices are really

1. Shave a tiny bit off of the HSF screws, but even then the leads would be close, so right now there's a good distance from the leads on the bottom of the MOBO.

2. Replace the HSF and modify the heatsink on the ram...


Really not sure what I can do. It's SUCH a small amount it's driving me crazy... Plus... I would still need holes or something for the airflow...

I was thinking maybe I could cut open an area for the HSF, as well as the ram, but not sure if that would look stupid. I was also thinking of upgrading to a bigger HSF and having it outside of the case, but that defeats the point of this case.

I really would like everything to be inside the case, without any holes, but that's doubtful. The HSF is right up to the top regardless, unless I replaced it with other fans, and was able to get enough air from the sides into the HSF but it's a big risk and very doubtful.


Not really sure what I should do... Sadly I've put this on hold for awhile, but really would lke to finish it. The Seasonic is too but, but I think the Pico will work, as long as it doesn't get above 160 (at l;east not for awhile). The scary part is that there is no protection on the pico's 12V rail I believe, so if you go too much over it could start a fire, which is ...... I just need to make sure I don't get above 160W, so I'll just buy a kilowatt meter and see how much it pulls... If anything I could do this with a skylake or another lower TDP CPU.


I really would like to get the height issue fixed.. I would assume all mobos would be similar with the height of the CPU socket, and ram... The only real issue is that there is a screw coming from the bottom of the cpu which is the longest "lead" coming frfom the bottom... Not really sure if it's connected to anything, but that's really why the HSF screws work well, but I don't know if I could get shorter ones...

So many issues, I really don't know if I can do this... I can ben dthe metal as well, but it doesn't seem to be working well...


Really not sure what I should do with this....


Thanks for all of the help, I will try to get some more pictures, and some of my main as well, to show off the fan setup, and the dust.



Dust itself shouldn't be too harmful until there is a lot of it... right?


I just had a bad experience with my first build failing, which I thought was due to overheating at first... So I'm a bit scared of this one dying too..

Thanks for the help:)
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Re: Motherboard grounding questions

Postby Karlsweldt » Wed Jul 27, 2016 6:14 am

After working with computers for more than 30 years, you do learn the "ins" and "outs" of proper design and operation. How the product and use has changed since first going public!

Extremely dry air can induce static build up on almost any material. Lower than 40% humidity level is about where the threshold starts. Synthetic materials, plastics and wool have the highest probability of static build-up.
If using nylon mesh like that from panty hose or similar, there should be a decent amount of dust kept out of the system. The material does not need to be "drum tight", but secure enough so as not to get sucked into the fan blades.. best over a grille. Very few places where there are moving parts that could be affected by dust build-up and cause a problem. But restricting air flow is not desired.

If you already have the proper I/O shield plate, then that is preferred over something 'home-made'. Yes, it must be electrically connected (fastened) to the main case, or have positive contact to shields on the motherboard ports.
Using wood panels to create a facade of sorts is allowable, for looks. But maintain some airflow space. Properly, there should be an entire shield around the electronics.

For CPU fans, there should be a minimal 2" or more of free space above them.. or they recirculate the warm exhaust from the fins. Ducting to alleviate this is a good thought.

RF radiation is very broad-spectrum, but most RF emissions from a computer are in the mid-band of AM radio. Unwanted RF emissions can be very low frequency, to extreme high frequency. Maximum RF signal is at the design frequency, but there is half-wave and quarter-wave lower and higher frequencies that also are present.
No, having a common radio near a computer won't cause damage. But a 'walkie-talkie' or other communications radio may interfere with operation.. Go back to the days of CB radio and OTA TV, its frequencies were right around where Channel 2 on TV band was broadcast! The CB radio could overwhelm the desired signal.

I would not 'shave' heat sink screws, as that may make mating of the threads difficult or failure prone. If the heat sink has spring-loaded mount screws, the extra thread length ensures proper and safe thread merge.
Definitely worth the thought of an opening above the CPU cooler, mounting a grille and filter there. May not look ideal, but performance before ambience.

Any suitable ammeter that has a metal sensor bar to wrap the wire around twice or more would be a good choice. No appreciable loss of current as with some shunt-type ammeters. Every multi-meter has a shunt-type sensor. For any current above 5 amps, a dedicated meter for that need is the better choice.

You might want to experiment with "doming" the case top, to create more free space.
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Re: Motherboard grounding questions

Postby LakaWaka » Wed Jul 27, 2016 11:22 pm

Karlsweldt wrote:After working with computers for more than 30 years, you do learn the "ins" and "outs" of proper design and operation. How the product and use has changed since first going public!


:) It's good to have someone who knows what they are talking about.

Extremely dry air can induce static build up on almost any material. Lower than 40% humidity level is about where the threshold starts. Synthetic materials, plastics and wool have the highest probability of static build-up.
If using nylon mesh like that from panty hose or similar, there should be a decent amount of dust kept out of the system. The material does not need to be "drum tight", but secure enough so as not to get sucked into the fan blades.. best over a grille. Very few places where there are moving parts that could be affected by dust build-up and cause a problem. But restricting air flow is not desired.


Interesting, so as long as I make sure to have a humid room for the computer it will work.

I will secure it with screws just before the fans. I wish I did this before, but wasn't sure if this would be good.. Should have asked earlier... I will try to get as much of the dust out as I can, there doesn't seem to be much, but hopefully I can make it good as new :).



If you already have the proper I/O shield plate, then that is preferred over something 'home-made'. Yes, it must be electrically connected (fastened) to the main case, or have positive contact to shields on the motherboard ports.

Using wood panels to create a facade of sorts is allowable, for looks. But maintain some airflow space. Properly, there should be an entire shield around the electronics.


It's technically an I/O shield, but doesn't exactly fit the entire width of the system, but the height is just perfect. How do I "electronically connect" it? on my first build there was actually a connector on the i/o shield, but the last few have not had anything light that, so I'm assuming just put on properly?

The one I have is really crappy and doesn't fit well. I will take pictures and let you have a look if you don't mind.

Well, the wood would be just enough to block the back and look nice. The sides are were the airflow really happens, but I could leave part of the back open, even though I want it to look really nice overall.


For CPU fans, there should be a minimal 2" or more of free space above them.. or they recirculate the warm exhaust from the fins. Ducting to alleviate this is a good thought.


Hmm, there is a fan in my case that is at the top with not much room, so I'll take a pic to show you if you don't mind.

I thought the fans only go one direction, either intake or exhaust? I have 3 intake fans in the front, so where does the warm air come from? What exactly do you mean by ducting?


I would not 'shave' heat sink screws, as that may make mating of the threads difficult or failure prone. If the heat sink has spring-loaded mount screws, the extra thread length ensures proper and safe thread merge.


Yeah... Not something I really wanted to do, but really need a TINY bit of extra room and it's making me sad... Granted, I'm sure that I need to place a hole at the top anyways so I can get airflow, but I figured smaller fans, instead of the bigger one, might allow for more room, and allow me to grab the air from the sides, but I don't know if a bunch of tiny fans would really be any useful...

Definitely worth the thought of an opening above the CPU cooler, mounting a grille and filter there. May not look ideal, but performance before ambience.


Well.. The main goal of this project is to put a computer inside this case, and I really didn't want to cut any holes into it, besides maybe cut out the letters for some led lights, and possibly help airflow.

I really am not sure what I want to do at this point, because I feel my options are so limited.

One thing that could be cool is doing a custom loop setup, but I'm not srue I want to invest tons of money, and not sure about all those chemicals and stuff......

IT woudl be cool.. But that's something for later.

There are smaller computers besides mini-itx, but I dont know if they would run a regular OS, or what, so I think Mini ITX is the smaller I got...


Any suitable ammeter that has a metal sensor bar to wrap the wire around twice or more would be a good choice. No appreciable loss of current as with some shunt-type ammeters. Every multi-meter has a shunt-type sensor. For any current above 5 amps, a dedicated meter for that need is the better choice.


Not sure what this quote is in reference to..?


You might want to experiment with "doming" the case top, to create more free space.


I tried bending the top a bit, but the problem remains with the sides. I also thought I could bend the metal flat, and then bend the sides a bit larger than before, but the problem comes with the front panel which I want to keep on it, and cutting the sides wont help.

Maybe I could rise one side, above the other, but I think that would look stupid too..


Not really sure what my options are?


Do I absolutely need air coming from the top?

Would I be able to switch out my cpu fan for smaller fans, or would that not work? I figure I oculd put a bunch on top, and some on the sides, and just intake into the cpu. The sides should provide plenty of air imo.

The only issue in that case... IS the stupid ram. I did find that the top pieces of the ram are bendable, so I "Technically" could break tyhem all off, and thus have space, but that's if I could use the smaller fans for sure, without having to open the top. Max open up the letters to add some flow to at least make things look nicer.

I guess one way is to test it out, but I figured I would ask your opinion on this :).


I would then want to go grab some new standoffs and then go fasten it to the case.

Then hopefully I could get some sort of ambient temp thermometer and put it inside my case to test some temps (depending if this unit actually has a build in temp sensor, but not sure how reliable they are)? Do you have any recommendations on a thermometer that would work for this situation?


Thanks a lot, please let me know your thoughts :).


Also a kill a watt meter to test voltage, then possibly get the pico psu. Speaking of that, did you happen to read over the specs on it? It should work for my needs, I did contact them and they seemed to suggest it would be fine for what I'm doing, but figured since you were asking about if I would ask to see if you had read up on it.


So really my best bet is the smaller fans and breaking off the top bits of the ram.


I guess it really comes down to what temps I'm getting in the end... right?


It's just annoying I have a very high TDP cpu, so I might want to maybe look into a much lower tdp, as that might allow me to do this much easier. I want to try with what I have on hand though, so I'm curious how it will go.
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Re: Motherboard grounding questions

Postby Karlsweldt » Thu Jul 28, 2016 5:16 am

I am not the only one here at the Forum with many years of computer experience. Many others, too, have long years of experience. Some are professionals, with their own shops.

Most I/O shields have springy tabs at some holes, to make contact with shields around ports. Some also have a metal tab or two to contact the top of port shields. Yet some I/O shields are no more than a thin plate with just holes.. relying on hard contact with the case. In the event of no proper grounding of the shield, a short length of wire could be connected with small screws to the shield and case.

All small DC fans have one rotation. They are 'brushless', being driven by a tiny servo motor. If a brush-type motor were used, it would create a lot of unwanted static and RF noise. Same with AC fans. Not intended for use inside computer cases!
The heat produced in a computer setup is from resistive loading on circuits and chips. The CPU and GPU are the major heat producers. The PSU is the highest heat source.
Cooling fans for a computer case should be installed so that there is more air forced into the case than drawn out. This is so the PSU is not starved for its cooling air needs.
The fewer count of fans, the quieter a system is. Too many fans, and it sounds like a bee hive in full-on alert!
Several small fans would require more current, and still not be as efficient as one larger fan.

As to measuring currents in working circuits, most ammeter designs use a slightly resistive bit of metal that causes a minute drop in voltage. The shunt has connecting wire leads at its ends, and feeds a volt meter which is calibrated to read amperes. The other type of ammeter has an aluminum bar that can be placed over or wrapped with the wire, and picks up the current flow by parasitic means. Either type can be almost 100% accurate.
That Kill-a-Watt device is a nice tool for the price, and has good accuracy.

Some older computer designs had a shroud over the exhaust fan by the CPU, and pulled case air over its heat sink and out. But with higher speed CPU types and more transistors on the die, a lot of heat is produced.. too much for that design. Ducting to the CPU fan inlet does still provide the most efficient cooling air source, from outside the case.

Motherboards do have temperature sensors, so too the CPU and GPU, and possibly the hard drive. Some high-end fans also have temperature sensors for speed control. They may not be as accurate as designed units, but do the intended job.
Altering the memory heat sinks will likely void their warranty. Do so at own risk.

You might want to consider a "mobile" class CPU. They are designed to go to an idle state when not processing data. Less waste heat, less overall current needs. For any CPU, it has a set maximum temperature limit. At this point, it would start to throttle down, or may even cause the system to halt until the temperature drops to a safe zone.
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