Hey guys, thank you for all your support.
In my case it wasn't about FSB, multiplier or memory. Simply the cpu I had couldn't handle more then 3.4. It had a wall for anything above, simply BSOD.
The new CPU is flying, 3.6 is easy at 1.45v (Small FFT's for hours). It likes both 8x and 9x multiplier. All other volts on stock.
ps. the new CPU always give me rounding error , no BSOD at all.
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