I built my system over 2 years ago with a MSI K8T Neo2 motherboard and AMD Athlon 64 3000+ CPU. I just upgraded my system to Vista OS, added another gb of RAM for a total of 2gb and installed a ATI 1650Pro video card. I want to also upgrade my CPU. The problem is there are 2 series of bios upgrades for this motherboard. The 3.* series and the 9.* series. I flashed my board with the 9.4 bios that supports the newer CPUs and it totally screwed up my system so I went back to 3.3. My question is what is the fastest CPU I can use with my motherboard and the 3.3 bios. Thank you very much. ~eddie