Video Card Trouble

[Gilles]

I recently upgraded my computer (computer A). I took my old parts and started building another computer (computer B). Computer B has my old video card, mobo, RAM, and CPU, and then an assortment of other used parts.

After building computer B I started it up and got no picture. I checked the monitor by plugging it into Computer A and it worked fine. I switched the cards in computer A and computer B and they both worked fine. When I switched them back, computer B stops working again (no picture at all). I tried another monitor and cable just in case and it didn't help. No idea what the issue could be except maybe a PSU issue?! I am using an adapter in Computer B. Note it's not the same as the image, it's only got one power cable instead of two.

Any help is appreciated. I'm going to try and take it to a store soon and have them diagnose it for me.

Specs of each:
Computer A
CPU: Phenom II X4 3.4 GHz
Mobo: ASUS M5A97
GPU: Radeon 6850
RAM: 8 GB DDR3
PSU: 600 Watt Silencer (I think)
Win7

Computer B
CPU: Intel E4800 @ 3 GHz
Mobo: ASUS P5QL Pro
GPU: Radeon 4870
RAM: 4 GB DDR2
PSU: 500 Watt OCZ
I will be installing XP

 

[MindoverMaster]

Umm, unless I misread that, that you carried over your RAM. DDR2 is not compatible with DDR3

 

[Gilles]

Maybe I didn't explain it well enough, but I'm not mixing any RAM, I know they're not compatible. My old RAM is with the old Mobo, and I got new DDR3 with the new Mobo.

 

[MindoverMaster]

Computer B has my old video card, mobo, RAM, and CPU, and then an assortment of other used parts.

This where I got confused

 

[PP Mguire]

Ok so let me get this right. When you have the other card in B does it work then? If so i would think there might be a problem with the card and mobo together.

 

[Gilles]

That's correct PP Mguire. What's so odd about it is that the GPU and Mobo had worked together for 3 years, and I've never heard of a Mobo and GPU not working together. I've had a faulty mobo before that was doing the same thing, but I don't think it's the mobo this time because my new card works fine in it.

 

[PP Mguire]

I was trying to type that on a tab and couldn't get out what I meant. Maybe the card isn't in the slot properly, or you might need to clean the contacts on the card.

 

[Gilles]

I've taken it out a number of times, cleaned it the best I can (without air), I doubt that's the problem, but I will pick up a can of air to clean everything.

 

[Gilles]

For those interested, there seems to be no solution. I have a video card that worked with a motherboard for years, and all of a sudden it refuses to work with it, but works fine with any other. The mobo also takes any other card. RAM has been tested, different power supplies have been tested, and different monitors have been tested. Nothing works. Lame.

 

[PP Mguire]

Have you tried clearing the cmos or tried different RAM? I know it sounds like a long shot but it could work.
I would also try taking the board and everything out of the case and laying it flat on something anti-static (motherboard box, anti-static bag) and see if the card works then.