[fortyseven]

U seem to be having a tough time dude! After reading ur story I cant say for sure what the problem is although I can tell you what its NOT. I doubt strongly that its ur CPU. Its not memory or graphics card. Also dont be using 64bit operating systems if ur system only runs at 32bit. The operating sytem is doubtfully the problem although I'd stay far away from Vista.
As far as motherboards go, I only use Intel. They've given me the least amount of hassle. My suggestion to u is three-fold. Apply the "back to basics" principle here. Take everything out of ur PC leaving only the four most basic parts: motherboard, CPU, RAM and HDD. Check to see if u get the same issue. If not, then one by one add another component until u get to ur problem. That should help u identify which specific piece of hardware is the offender (this assumes that the problem is hardware related).
Secondly, Im not sure at what bit depth and Hz ur working with but as suggested earlier, keep to the standard 16bit 44.1Khz for now. Once u have determined exactly what the problem is then u can increase it if u like. Thirdly, I'd update all system drivers, especially the chipset and ASIO ones.
Remember with computers, sometimes things that should work dont, and sometimes things that shouldnt work do! So just because it ran on someone else's pc doesnt mean that it will definitely run on urs. Even 2 identical pc's never run exactly the same.