The ASUS P5B Deluxe P965 I have supports the E7600 according to ASUS's CPU support list. A BIOS update to one of the later supporting versions is required. I have a Q6600 65nm running great in my P965. The P965 was released well before 45nm and early rumors of 'problems' regarding the performance of 45nm units on the P965 were regular. The HP board will have a grayed out BIOS with no overclocking abilities at all. I repaired a system using the board and even the speedstep feature was defaulted on and a nonchangeable part of the BIOS HP provided.