HP Pavilion Slimline s3507c Desktop PC won’t turn on

Alright well i’m trying to fix this HP Pavilion Slimline s3507c Desktop PC but seem to be getting nowhere with it. ALL the lights turn on but the screen stays black, doesn’t POST or anything yet I can feel the hard drive starting up and the CPU fan start to spin. It stays on like that until I hold down the power button to turn it off. SO it doesn’t turn off by itself, it needs physical intervention by me in order to turn off.
I have done the following to try get it to turn on,
Inserted a NEW video card because I thought the on-board VGA adapter had gone bad and that’s why it wasn’t getting anything in the screen. No change.
Tried 1 stick of ram at a time, no change.
Reseated the CPU, no change.
Cleaned out every dust bunny there was. No change.
Just had the HDD connected, no change.
Just had the video card connected, no change.
Took off CMOS battery. No change.
I’ve run out of ideas. Like I said all the lights turn on and I could feel it powering up but nothing shows on screen even with the new video card. Yes i’m sure the monitor isn’t the problem because i’ve tried it on 3 separate monitors and they all only showed a black screen.
It was working flawlessly for a week ( I just installed windows 7) and my friend was on yout ube when the screen went black. I turned it off and tried to turn it back on but nothing showed up. No post no nothing. SO i’m really stumped.
THis thing has no warranty so i can’t go to HP for answers.
So any ideas on what could be wrong?
Answer #1
Looks like the motherboard crapped out on you.
Answer #2
yea i was thinking that’s the problem. Just wanted to make sure I wasn’t the only one thinking that. Anyone got any other ideas of what it could be? I mean I was 97% sure it was the graphics adapter because I had seen this happen before on a couple other computer, there would be no image but the computer still turned on. Just pop-in a video card and it would work again. But like I said I tried that but still nothing. Now i’m also 98% sure it’s the motherboard because there’s hardly anything else I could think of that it could be, but I was wrong about the video card theory so I might be wrong bout this too.
Answer #3
yea i was thinking that's the problem. Just wanted to make sure I wasn't the only one thinking that. Anyone got any other ideas of what it could be? I mean I was 97% sure it was the graphics adapter because I had seen this happen before on a couple other computer, there would be no image but the computer still turned on. Just pop-in a video card and it would work again. But like I said I tried that but still nothing. Now i'm also 98% sure it's the motherboard because there's hardly anything else I could think of that it could be, but I was wrong about the video card theory so I might be wrong bout this too.I’ve seen this before a few times. It’s always the motherboard
Answer #4
Alright, motherboard it is then. Oh well. Time to look for a replacement. Thanks man. This week just isn’t going my way, car started giving me problems the same day this thing f-ed up. FML