My girlfriends computer recently began to act up, specifically the monitor would randomly flicker off, then back on. While this wasn't worsening or causing any major issues, other than irritation, I replaced her video card recently thinking it might fix the problem (also, I upgraded as she wanted to start playing video games on it her PC again and the old card was a joke).
However, once the new card was installed her monitor suddenly started to lose signal and not come back, requiring a hard boot. I thought that perhaps the monitor itself had died, as all of these problems started occuring right after a move, and the monitor suffered a fall in the back of the moving truck sadly. So I went out today and purchased her a new monitor, not thinking that the problem may lie elsewhere. However, after setting up the swanky new monitor for her, the problem persisted. I switched out DVI cables, checked to see if it was a problem with the new video card by switching to the onboard video and I also reseated the ram and unplugged and reattached every cable, thinking it could be a loose connection from the PSU.
After I reseated all of the cables and Ram, all of a sudden the computer wont even post. It powers on and all of the fans run but it wont go to BIOS at all, nor does the monitor receive signal. I tried reseating everything again, and I also popped out the CMOS battery to reset that, still nothing.
Also - I'm not sure why I didn't think of this before, stupidity I guess, but I just hooked up the old monitor to my PC and it's working fine...
I'm really hoping this is just a PSU issue, because I can't really afford to purchase a new M/B or CPU sadly.
SPECS: everything byt the vid card is a couple years old...
M/B - ASRock ConRoe1333-D667 R1.0
Ram - 2.5 gigs DDR2 generic brand, one stick is 1.5 gigs, the other is .5, I believe
CPU - Pentium 4 3.0
VG - GeForce 9800 GT (brand new)
PSU - Green 650w
There are 2 sata HDDs, a sata dvd burner and a multi-card memory reader installed as well, but that's about it for components.