I've only got experience with two mobos with my Prescott. Initially tried my IC7 and it did pretty well after I flashed to the 21 BIOS. Figured the AI7 would do better since it officially supported the Prescott. But, the PWM (mosfets) run lots hotter on the AI7. I've spend a lot of time and effort in vain trying to control motherboard heat with the AI7. So, I switch the Prescott back to my ol' trusty IC7. Looks like the AI7 is working out much better with my 2.4C M0 stepping processor and KHX PC3200 BH-5 RAM.