From the alpha website.....
NOTE 1 : The PAL8045 will fit the A7V266-E board without modification. However, it will contact one of the board's capacitors, POSSIBLY damaging it. Rounding an edge of the base with a DREMEL or other tool could be a possible solution. This would, however, make you heat sink non-returnable. Due to these issues, we consider the use of the PAL8045 on this board a "Use at your own risk application.
I had to Dremel mine to fit the Shuttle AK31 v 3.1 not that big a deal for me but there are plenty of other great HS's out there that might not fit....If you do dremel, make sure you remove all aluminum filings before mounting.
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