Motherboard and graphics card.

[Acepilotf14]

Wondering what a good pair would be with 3gb of ddr2 RAM I already have. The current motherboard I have doesn't have PCI-E slots, and obviously that's a problem. For now, no limit on cost.

 

[Asus]

and your CPU?

 

[AtomicSpark]

Are your RAM the same speed and latency? If not, you're asking for trouble.

 

[Acepilotf14]

Celeron D 3.33ghz CPU.
Dual-Core Proc.

 

[Saturos]

A Celeron D? Hmmm. old stuff, but still works I suppose.

You should be fine as long as you choose a motherboard that supports ddr2.

If at all possible, do what the others said and pick a motherboard that best suits you RAM speed.

Although I don't really think RAM speed is a big issue tbh unless your swapping different sticks of RAM.

Better safe than sorry though.

 

[AiM]

I went with the Asus P5Q-E for my recent comp. But as a whole, the P5Q series is consistently rated quite well. I was originally going with the PRO version but the E was on a ridiculous sale so I went with that instead. Motherboards, from what I gathered, doesn't really affect FPS much so I went with a more feature-orientated focus. Quadfire capabilities, 16 GB ram limit, energy savings, etc.

As for Video cards, the general consensus is that the ATi 4850 completely dominates in price / performance. Considering the fact that you're only paying $200 (without rebates) and yet it's capable of running Crysis at Ultra High settings, I think it's a pretty sweet deal. You may want to get the 4870 if you have a bigger monitor though. Of course, with the recent Nvidia price slash, the 9800 GTX isn't a bad deal either since it's in the same price range as the 4850 now when it used to be priced a tier higher.

If you do go with the 4850, I'd recommend getting the new MSI model that comes with revamped cooling. The 4000 series is notorious for running pretty hot for having a bug in fixes fan speed at 30%... but there are outside fixes to use until ATi releases an official fix.