CPU Overheating in System

[RSheasley]

Emachine computer I recently looked at with shut down issues (yea I know they are junk many times). It has an Asus built 939 socket
motherboard in it, a Athlon 64 (3500+) 2.2 ghz 939 socket CPU and rear case fan. I cleaned the system thoroughly the first time (smoker with dirt everywhere). I ran it just fine for over a day with the CPU temperature never getting higher than 35 C. He took it back to his place and it started happening again (CPU shows over 55 C regularly and then spikes to 70 C). I asked if he was covering over the side panel and some other things. So I replaced again the thermal compound (Zalman Thermal Grease) on the CPU, tried a different rear case fan, and finally another power supply. All seemed to have the system run a bit better. There is no room in the front of the case for any fan just some vents. I also checked the bios settings and there is a few for the temperature- the max before the unit is to shut down so CPU does not get damaged, a fan speed setting (to try and increase the fans rpm to cool it better). CPU fan went from around 1800 to 1900 rpm up to over 2000 rpm and the other fans (power supply and rear case) seem to be at 2400 to over 2500 rpm. Today it had shut down again. This system originally had a Athlon 64 (3200+) 2.2 ghz cpu in it from the factory specs.

So I am thinking a new CPU fan (with the original factory phase change
material instead of the Zalman Thermal Grease I have been applying or
another CPU (should I go back to a 3200+) in the system (plenty used
listings on Ebay), OR both maybe.

Any recommendations on better after market CPU cooling fans/heat syncs for those Socket 939 boards?

[evasive]

Asus have a bad rep for measuring temps in the bios.

eMachines have a bad rep for their power supplies as well, usually utter cr*p. What is the brand/model power supply in this one?

[Karlsweldt]

Find out how the computer is situated. If within a foot of a wall at the back, or in a corner of the room, the exhaust air from the case can be sucked back into it.. raising temps quickly. Best is having more than 2 ft. space behind the case.. even more. If not practicable, then fashion a diverter out of a small thin box, to direct the exhaust either up or sideways. An empty macaroni box or similar would work well. Remove the top, cut out one side hole (where the exhaust fan meets). A bit of duct tape holds it in place.
Sounds too simple, but does work wonders!
True, almost all PC cases have no provision for adequate front vents. A custom auto body shop might be able to do a series of small louvers in the side panels, if desired. Otherwise, a 6" fan opening in the service panel side would provide proper cooling. But it would need a metallic screen guard to avoid excess RFI emissions.
If there is also a rear case fan, it should push air into the case.. not draw out. Otherwise, the PSU could be restricted of its cooling air flow. The ideal ratio of air flow in a PC case is 1.5:1 inlet versus outlet. This helps keep debris out of the optical drives.

[RSheasley]

Power supply is not one of the Emachine OEM's. First supply in it was a Hipro, second one in it now is another brand- which I can't remember at this moment.

As for where it is sitting, it is less than the 2 feet you mention Karlsweldt. In the corner of the room. Similar Emachine that only has a Sempron CPU in it runs just fine in the same area...

So no recommendations on Socket 939 CPU coolers?

[evasive]

You could try and cleaning both the CPU and the heatsink from any paste/pads/whatever, apply a THIN layer of thermal paste and try again.

However, I think the original heatsink just isn't up to cooling that 3500+ even though the thermal characteristics are similar or just half depending on what 3500+ you got exactly.

What is your budget for a new heatsink/fan?

[RSheasley]

Evasive,

Thanks for the reply. I had cleaned the CPU and fan 2 different times in the last week, once before when I did the initial cleaning- this was the first time and only covered the CPU (see many times that the paste is all dried or not effective). The system as I stated was run for a day with CPU under the 35C temperature. Second time I took the fan off then again when the system was back at the other location, this time I did a thin cover of both the fan and the CPU. At the same time, I replaced the rear case fan and had tried the different power supply.

Budget at this point is probably under $30 or so, and I may still try and see if there is any bios updates and capability in the bios to step down and underclock this CPU back and run it for a few more days that way.