Question Odd Display fault with old please


Well-known Member
Hi all, not sure if this is the best place to post this question.......please advise if there is a more suitable forum.
So, today i kinda stripped and cleaned my in-law's ageing desktop pc, didn't remove motherboard / cpu / memory / or drives, but removed and cleaned cpu cooler / replaced thermal paste, brushed mobo down with my trusty paint brush along with dusting off hdd, case, rear case fan, and taking the plastic front panel apart to dust. Motherboard is an old Foxconn G31 socket 775, cpu is Core2Duo E6300, memory is 2 x 2Gb DDR2 800MHz. I also installed a new SSD to speed things up a bit.
When i booted the pc i entered BIOS to change boot device to the cd drive for a fresh install of Windows 7 on the new SSD, saved changes and re-started the pc. It ran through post and BIOS start up screens, although each screen seemed to fade in on the monitor a little late, then displayed the Windows is loading files screen, at which point the display just seemed to fade out to a blank screen.
I let it run for a couple of minutes as the dvd was spinning, and hdd activity light was flashing fast as expected during os install. I then shut the pc down with the power button, and tried re starting the pc, no display at all on monitor, although it was receiving a signal (light on monitor stayed green).
I thought maybe the monitor had died (it's an old thing i use for testing), so tried it on my personal pc, it was working fine. To this point i had been using on-board graphics via mobo VGA port.
I then tried 2 PCI-e graphics cards, via hdmi to my tv, signal passing, but no displayed image on screen.
I powered off the pc, removed graphics card, removed BIOS battery fora couple of minutes, re-fitted BIOS battery and re-connected to on board vga port and my test monitor. Booted pc into BIOS display working fine, set BIOS to "optimized defaults" saved and re-booted. An image appeared on display briefly during bios splash screen, before fading to a blank screen again.
So, i tried replacing the power supply unit with my spare "test unit", re-set BIOS and re-booted pc.
Again i get good strong image on monitor, enter bios, and run through settings before saving and re--starting, again i get display briefly during boot which fades out to blank screen.
Has anybody solved a similar issue, or have suggestions for other things i can try?

Thanks for looking


Distinguished Member
Seen as you have reset the bios you might have to change the output to the discrete gpu
it may have change to the IGPU with in the bois and now it's (enabled) as it is on by default now .
just a thought .


Well-known Member
I have tried setting BIOS to initialise on board graphics first, as was set to PCI first after re-set.
Can't see any other settings re graphics :(
Thanks for taking the time to reply though.



Well-known Member
OK, so i pulled pc apart and have been playing with a minimal set-up on the bench.
If i re-set bios, the onboard graphics work, and will stay on for as long as you stay in bios. As soon as you exit bios display fades out to blank screen.
It does exactly the same with a gpu fitted :confused:


Well-known Member
Resolved, although i tried the monitor i was using on my own pc, and it seemed fine, it was actually the monitor which was at fault.


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