Laptop troubleshooting forum: Black Screen problem HP pavilion DV5-1004nr

I will tell the whole story of the problem, please excuse my long windedness, but I know how important details are in diagnosing PC problems.
My Wifes HP Pavillion dv5-1004nr came with Vista 64, but I upgraded it to Windows 7 home pro 64 with no problems. Link to the lappy for specs (http://reviews.cnet.com/laptops/hp-pavilion-dv5-1004nr/1707-3121_7-33088546.html)
It was sent in once while still under warranty to have the thermal bonding on the CPU replaced, b/c of overheating. Over heating was fixed then.
About a month ago it began to have screen problems. The whites on the screen took on a flickering blue tint. When plugged into an external monitor there was no problem with color on the external (the problem still persisted on the main monitor).
I installed new video and monitor drivers with no change. I installed new bios with no change.
I did some research and concluded it was likely the internal cable that connects the motherboard to the monitor (whatever that thing is called). I never got around to replacing it.
The problem persisted, and got worse. The screen began to occasionally flicker white, for maybe 2 seconds at a time. Then finally after the recent Windows 7 updates (on 4-14-10 I believe) the screen began going solid black about a minute after start-up. The rest of the laptop seemed to be functioning fine. I transferred a bunch of flies off if it while it had the black screen. There was no cursor icon at this time.
I booted in safe mode, which seemed to keep it from going black, and my wife restored to the last restore point. After that it failed to boot completely. You could see the windows logo, but then only have a black screen with a white cursor (which I could move). It would not respond to control alt delete, or any other commands. Booting in safe mode and in low res mode did not help.
So here is where it gets weird. I put in an Ubuntu 64x disk and run it in live mode. The screen worked perfectly, as did everything else. There was no color problem with Ubuntu, at first. For about 4 hours the colors were fine, then the blue tint returned.
Then I restored the PC using a system image I created from January right after Win 7 install. Again the screen worked perfectly for about 4-6 hours. Then the blue appeared again. Now it has begun to flicker white.
I was convinced it was a hardware problem, and still am. But I am puzzled that changing OS seemed to delay the problem from showing up. Not sure why that would be.
Anyway, any help or advice would be appreciated.



Other Details:
We use Avast, it is updated, but it has not found any viruses. I doubt it is a virus issue anyway considering system image was from January, and Ubuntu had similar issues.

I have reset the Laptop, unplugged and removed the battery, held the power button for 30 seconds.