The processor will work just fine, though as I discovered some other commonly used components on newer systems might give you some trouble so it pays to consider the whole system:
http://www.zdnet.com/zdhelp/stories/main/0,5594,2218754,00.html i believe i saw Ingo Molnar P III patch which does two tihngs: 1. faster context save/restore during the switch (FXSAVE etc) 2. SSE stuff included into context check lk mailing list OK