I just built a system with the A7V333 and an Athlon 2100. I have 768 MB Samsung PC 2700 Cas 2.5. I tried running it in "turbo" mode at 2.0 and the system worked right before Windows booted. Right before windows booted the system restarted. I hope this ill fated attempt didnt damage my DRAM It works in 2.5 mode still. Could this damage the DRAM? Would you see a big difference between CAS 2.0 and 2.5? Correct me if I am wrong, you might be working with some high end program that needs it and see a difference, but, me? heh, I'm just a gamer.