Well, you're pretty much looking to change the ram as well unless you stick with socket 939. (DDR versus DDR2) Also, do you have AGP or PCI-e for video?
If you stick 939, you're going to need a 4000+ to equal your performance (2.4ghz, 1 meg cache) as far as a single core chip. Obviously, you want dual core.
939, you're looking 4600+ or FX-60.
If you go AM2 or 775, you need to get new ram in addition to your other parts.
AM2 sweet spot will be 4600+ or 4800+. That same money gets you into an E6400 which gives you much more overclocking headroom, and also great standard clocked performance.
Ram, go with PC6400 DDR2. Don't worry too much on latencies.
Board, go Asus or Abit. Match it up to your video card, or what you want to run video card-wise. (SLI, Crossfire, Single Card... )
Hard drive, 250 or 320 gig, WD, 16 meg cache.
Originally posted by: ohgod123
To make a long story short, I've had blue screen and fatal error problems return to my computer 4 weeks after changing my RAM and formatting to add Windows Vista. Everything was fine but I now really think it is a hardware problem, so I'm looking to replace these components. With 500 max to spend, what do you guys recommend for mobo + cpu + hd replacement?