Overall, I have been and continue to pleased with this PC. I am what I would consider a light gamer, though there are couple of newer games that my PC is struggling with. I'm fairly certain a video card upgrade will cure what ails me.
For the moment, assume that price is no consideration ( ). What is the best card I can stick in this thing without one or more of the other components creating a bottleneck?
If money is no object, I'd get an ATI 1950 pro AGP, which is probably the fastest AGP card around now, having supplanted the nVidia 7900 GS. I'd also recommend getting one sooner rather than later-AGP is dead, and I don't expect ATI to crank out a boatload of these cards when their PCIe cards are selling so well. These cards are also clocked identically to the PCIe versions and aren't too big of a power hog, although they do use a little more power than a 7900GS, but still within your specs I think, unless you have 12 HDD. Bottlenecks be damned, I say in your situation - overclock your Barton, or get one of the last of the AMD 939 chips and use your RAM on a cheapo board.
I picked up a 1950 pro PCIe today for $200 CDN, it schools my 6800GT AGP. I have an Asrock 939 dual sata board which lets me run both cards at the same time - the display possibilities will give me something to play with for awhile.
Supposing your current powersupply is adequate and has the right amps per rail, with reliablity, then the graphics card muffin suggested is currently the best right now. And he meant 7800GS not 7900GS (7800 is AGP, 7900 is PCI-e) Your processor seems fine, I think it'll last till your done with the computer for good. Have fun
In addition to the PS question above, I have two final questions about the graphics card. Several of ATI's partners (VisonTek, Diamond Media, Sapphire, etc.) have or will be coming out with X1950 Pro AGP cards.
Does it really matter which one I choose if the specs listed by each are the same?
Also, I've noticed that some offer memory of 512MB vs. 256MB. Based on what I have read on THG, the difference in perfromance would be negligible in most cases. Right?