I opened up my computer to move the audio cable that runs to the front of the machine (the graphics card EM was causing noise on the line). Was pretty careful not to touch anything, and didn't unplug or move anything else.
When I pugged everything back in and went to reboot, the computer started up and gets to the windows loading progress bar (though in a very low resolution version). After the progress bar completes the screen goes black as usual but then the monitor turns off (not receiving any output from graphics card) but the boot progress seems to continue as normal (eventually the windows startup sound plays).
Things I've tried:
Jiggling and re plugging the power cables etc.
Replacing the graphics card (with an old one, which wouldn't display anything).
Clearing the CMOS (both via BIOS and hard reset by removing battery for 5 mins).
I'm running out of ideas, is it likely the motherboard is fecked? Any other suggestions to fix it?