Question : Problem: No video from the computer

I have a PC here that I was trying to fix.  The PC is a Gateway Media Center.  The issue was that the video card on the motherboard was creating bluescreens and displaying lines in the picture.  Therefore I inserted a new video card and told the BIOS only to use new video card.  The computer turned off and on and worked just fine for 2 days.  Then I turned off the computer, set it in my drivers side seat.  Took it to the home it belonged to and plugged it in and nothing would show on the monitor.  It turns on, the lights show up, and fans buzz.  However nothing, not even the BIOS displays on the screen.

So I tried another computer on the monitor and the monitor works just fine.  Brought the PC back home to work on and still there is nothing.  I inserted another new video card and still there is nothing.

Any ideas on why nothing displays on the comuter?

Answer : Problem: No video from the computer

This doesn't look great - let's remember we started with an integrated graphics chipset on a motherboard that was throwing blue screens.  That's still the backbone of the machine even though it has a new graphics card.  You'd not opened the case between packing it in the car and finding it didn't start (or even POST) so we've got to think something moved - either because it wasn't secured or because it's cracked (PCB or solder joint).  Movement can cause one of two scenarios :

1) A contact that should be there is broken

&

2) A contact has been made that shouldn't have

You've already checked that everythnig is securely connected so is there anythnig that has moved and may be making a connection it shouldn't (the most common is the motherboard touching the case)?

One other thing I'd try before giving up on it would be to jump reset the BIOS incase it's been messed with trying to detect something that had moved but with no POST beeps at all this is only an outside chance.