if your borking OSs then it is likely memory or memory related. what SPP voltage are you running? can you run high FSB with memory un-linked at 800MHz type thing without borking an OS. the first 2x1GB kit of memory i started clocking on this board had me corrupting OS every second boot until i figured out what the board liked. then, the first 2x2GB kit of memory i clocked had me in the same boat...again, once i found out what the memory could handle, i can control issue. i also find Vista will go to shyt a lot easier than XP x64...pretty much why i am clocking this Mushkin kit on x64 now that i am really pushing it.

list a specific setting that you are having issues with (guaranteed to bork the OS with a couple of boots/reboots), along with all your voltages, memory timings (secondary as well), etc...and i will try to repeat it on my board. should be much easier than trying to diagnose the entire FSB range.

*BTW, Mushkin Ascent 2x2GB CL6 clocking almost done. they scale right up to 2.20v (actual) and have officially spanked the 2x1GB PC3-16000 Ballistix that are in my signature for dual 32M SPi at 6-6-5