Black monitor on startup (no post). Comes on for XP loading screen

[TimeWarrior]

Hi Guys,

I am having a strange problem with my pc. I borrowed its PSU the other night to test some other gear but since I put it back in I have been having this problem. When I press the power butter there is a slight pause, the keyboard lights flash as usual, single beep as usual, numlock light comes on as usual but bios doesn't. After a wee while with a black screen the windows loading screen comes on and windows starts as usual. I have tried resetting the CMOS, I have checked all the power and HDD plugs and even swapped some. Another weird thing is that if I press delete as though I want to change bios settings I just have a black screen...
I have a mild overclock on the processor which I will try clearing, I will also try the other DVI plug. Any help/thoughts will be greatly appreciated.

Time

(I have shifted this from the motherboards section as no suggestions have worked so far.)

 

[masterjaw]

Have you tried initiating the setup bios screen (via del key or whatever) to check if the screen just didn't pop out and you might be in a quick boot setup?

 

[TimeWarrior]

Yea I tried that. It's as though there is no video signal until windows starts. If I leave it the monitor comes on for Windows loading, if I press DEL (my BIOS setup key) I get a black screen until I press rest. I've noticed something else though. I press power, NUM CAPS and SCROLL flash. NUM comes on... nothing happens. Lights flash again. This time NUM off... Windows loading. I don't know if that means anything - it's as though it's booting twice and the second attempt always successful BUT no post and Windows loading comes up immediately (making me think it was already going). When I have some time I will try everything out of the case.

 

[TimeWarrior]

Solution was to swap out the graphics cards between my own and another computer, boot them up normally, shut them down and then swap them back.