Now I have tested different settings for Skews, and anything between 300 and 500 gives opportunity to boot at fsb498, while not possible otherwise. I also noticed that my core nr 1 and 4 are the strongest, while core nr 2 and 3 are weaker. So I have to sets of cores on the same level each. What I did was to try and change GTL values for cores in pairs. Ended up with GTL1:0.67, GTL2:0.63, GTL3: 0.63 and GTL4: 0.67. The result is: before, core 2 and 3 errored while priming at fsb495, after, all 4 cores priming with no errors. I still get random crashes and BSODs at fsb495

Can anyone test if the things I mentioned in the last two posts work for you guys to get more stability on the edge? I still feel like there is no recepy for stable 500 on fsb, but I think I will use what I learned so far when going for higher CPU speeds