<< it's 80mm x 80mm, right? So is the Alpha PAL8045, which fits perfectly. IMO, the PAL8045 is a much better heatsink in that it is more stable and its build quality blows almost any other heatsink out of the water! >>
Have you had any personal experience with the AX7? Right now my roommate is running the AX-7 with a very low flow panaflo on his XP1700+ oced to 1900+ and is gettting temps in the low 40's under full load.