I have an ASRock 939 Dual-SATA2 MOBO with a AMD Athlon 64 3200 processor. I have 1024 mg of ddr ram. My video card is a Nvidia GeForce 6800 GS (agp). I'd like to upgrade my CPU and I'm confused as to what to get. The MOBO is socket 939 so I could go with the Athlon 64 series, the XP series or the 64 X2 series. My mobo has an AGP and a PCIe slot I may someday upgrade my video card to a PCIe card. I am a casual gamer, mostly 1st person shooters. Doom3 - new half life - Quake 4. I also do a lot of work with music files. Currently converting my records into MP3 files. AND - I'm trying to stay at about $250 or less for the CPU. So we're talking the Athlon 64 4000 - the Athlon 64 X2 4400 - or the Athlon FX64. Which one will be best for what I'm doing with the computer? Thanks!