Upgrading a stock HP

[OnWithTheShow]

Sorry for the OT post but this forum gets a lot more traffic than the HP forum. Anyway my brother has a HP mediacenter M8330F http://h10025.www1.hp.com/ewfrf/wc/document?docname=c01312600&lc=en&cc=ch&dlc=de&product=3644705&lang=de
that bottlenecks really bad on modern games. I reviewed the specs and think most of the problem is in the video card. I was thinking of getting a GeForce 9800 GT http://www.newegg.com/Product/Product.aspx?Item=N82E16814127387

I have them taking a picture of the inside of the case for me so I can make sure it will fit.

Is the axiom that memory should be installed in pairs still true? This system has 3 1gb sticks so I would get a fourth (actually get two so they will match) if it is still true.

Any other recommendations?

 

[alvine]

does your power supply have pcie connector? also make sure it has pcie slot before you buy, I bet it does but just make sure.

I would personally go for ati 4850, faster than 9800gt since its exact same as 8800gt just a dieshrink.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814102770

 

[OnWithTheShow]

The board has a PCI-E x16 slot (currently used by the stock video card) so I imagine it has a PCI-E power cable also but I will check.

 

[Proximon]

You might get some slight speed increase on the memory, but if it's a 32 bit OS you will not get much more actual usable memory. Maximum usable memory in 32-bit XP or vista is around 2.8-3.4GB, depending.

You may not want to use that exact card because it will dump it's hot air inside the poorly cooled HP case.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130397
or
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161244

Would be good choices, but you may need to upgrade your PSU as well.