I had a slot-1 750 and a P3B-F that was still new in the box (bought it like 2 years ago). Windows XP installed with an ACPI HAL.

If overclocking is your major concern, the BE6-II is indubitably the way to go, the control you have with those are just awesome. I used one to get an original 750 to 900 no problem. The P3B-F has ...