Quote Originally Posted by tekjunkie View Post
There was a known issue with 1600QDR/400FSB and I believe it still exists with even the recent BIOS versions. I for sure can't run my QX9650 stable @400x10 for 4GHZ, So I am currently @ 445x9 for 4GHZ with absolutely no issues so far(10 hours priming/10 hours OCCT and currently running F@H). So try increasing your FSB a tad like 402/1608. It used to work with the S2E that I bricked, but I haven't tried it with the replacement that I got.
Funny, I already built 2 rigs with a QX9650 and S2E that ran 400*10 perfectly

The issue here isn't just one of those darned FSB holes, as problems happen with all combinations of FSB/ramspeed I have tested so far, except the 1333/1333 linked sync stock setting. Bios defaults is even unstable lol. I wanted to run FSB 1700 (= 4Ghz on the E8500) and 1600 mem like it's rated, but like I said no go. Stock FSB and 1600 mem isn't possible either