Hi , hoping somebody maybe able to help with this problem. I am running an E6420 on a Gigabyte 965P-DS3 with F13 BIOS updated from F10 which had a dodgy PCI lock.

Basically I've had this machine about 10 months, originally put it together with overclocking intentions but at stock it was so much faster than my old machine that I just left it. It's been completely trouble free at stock but now I'm looking to push it just a little it's not having any of it.

Any BIOS increase in FSB causes problems with the video output, even a 14mhz FSB increase will result in display loss after random periods, however the system is still completely stable in all other regards ie. Vista will boot, shutdown ect. I can hear it, just can't see it .

Strangely if I use Gigabytes Easytune software for overclocking in Windows I have no issues with loss of output and can push it up to 2.66ghz without breaking sweat, but try putting those setting in the BIOS and poof graphics won't even initialise, but system will boot as if nothing is wrong, I reboot and the graphics starts this time but cuts out just as Windows finishes booting .

Also I have tried with various settings in the bios ie. PCI-E Auto/locked@100/101/102mhz and with +0.1v results varied but video was always lost after random periods of time.

I have no idea why this is happening, so hopefully somebody here maybe able to shed some light.. Pleeease .