The Mother Board

I am currently looking to do some upgrades on my parents computer, but unfortunately it happens to be a Dell computer, for which they have lost all the pertinent paperwork. Upon opening the case I found the following serial/ID #'s:
Dell C9U USF2
E219542 W-2
SHO821 Rev A04
DS-N CN-0UW457-69861-74E-122A C-O CN

When I searched the E219542 number I found a Dell Optiplex GX280 SFF Motherboard # Y6281 / E219542, however the accompanying picture does not match the motherboard actually in the computer. Some further searching found a visually identical, so far as I can tell, motherboard but it is listed as a Dell Dimension E521 Motherboard HK980. Is there any way to determine which is the board I am actually working with, and what are the possible specs for it? Specifically how much memory I can install and use with Win7 and whether all the memory sticks need to match the current 2 sticks of 512 MB, and what video card I can install to help this slow machine out.

The only BIOS info I can get off the boot page is Dell 1.1.8, which so far has yielded no further information.

Welcome to Motherboards.org!
May be a Dell model GX270 per this Dell link.
There should be a service sticker either on the back of the case or on the bottom. It will have a model number and service number for reference. That is the best way to find out what the system was built as.
Some motherboards are used in many models.. others are more dedicated to specific models. That service tag will be your best resource.
With the smaller computer cases, only certain motherboard designs will fit. Same with the power supply. If a mid-tower or full-tower, the choices are much broader as to upgrades. But many products from Dell and HP are dedicated designs, and only specific replacements or upgrade parts are available.. some times only from that OEM source. Dell and HP (plus other brands) do not make their own motherboards.. just assembly of the systems. But when an OEM company places an order of several thousand motherboards, the parent manufacturer will gladly make production runs of different designs! They may be nearly identical to OEM setups, or much different.

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On the outside of that Dell casing there is the system model number, from that you can readily find the replacement board and/or any documentation/drivers for it. Finding the original manufacturer can be troublesome as Karl indicated and usually there is no support from them in the first place....

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We hate rut, but we fear change.
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System error, strike any user to continue...

I appreciate the information, I will check for those stickers next time I am working on it. Besides a general google search, is there anywhere specific you can recommend for looking up the info provided on the service stickers?

Nope. They're Dell specific.

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Faster than the speed of snot

Two wrongs don't make it right, but I sleep pretty good at night

if you have the service tag just go to the Dell support, site, put it in, it will give you the info for the system. Based on the system we can give an educated guess on what is inside.

_________________
We hate rut, but we fear change.
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System error, strike any user to continue...

Ok, I have checked your info and it comes back as being used inside the Dimension E521. Maximum 4GB total. Crucial usually have their info in order

http://www.crucial.com/store/listparts. ... ion%20E521

As for the video card:
http://accessories.us.dell.com/sna/pfyd ... sisid=8245

The maximum I see in there is HD4670 which is because of the 305W power supply. The board is BTX which means cannot be easily replaced, same for the power supply... With 4GB and HD4670 card it will run faster, especially with a fresh install of windows.

_________________
We hate rut, but we fear change.
********************************
System error, strike any user to continue...