Hi,

for max FSB try a Gigabyte P35 Board. I tested my E8500 on 3 Asus P35 / X38 Boards
and all do max. 550-555FSB, on Gigabyte P35-DQ6 did it 580FSB!

But nice results, my E8500 is Week L738 and can do max 5016Mhz for a valid, 4.84Ghz
SuperPi 1M and 4.75Ghz 32M SuperPi 32M with watercooling and max 1.65v vcore