Hi everyone,
first thanks for this place, it's wonderful to see how much people can be passionate by their hardware.
Secondly, excuse me for my english i'm a french baguette and i haven't studied english enough to write it perfectly.

Now here's the problem i've a X58A-UD3R V2.0 (FB Bios) paired with a x5650 OC @4Ghz / QPI=1.36; BCLK=183mHZ; cpuV=1.28 with HT on

i want to update bios because i want to use VT-D technology, only Fh1 bios from Gigabyte Techs support this features.

So i flashed Fh1 Bios through @Bios (i know it's bad), flash was ok and my system boot with any problem but i can't overclock anymore every option i touch make the system unstable and dont boot (like simply decrease ram freq make the system unstable).

i tried other bios, they do same thing no overclock.

I can overclocking ONLY with FB Bios

thank you for your help