I'm getting garbled graphics on my computer in text mode environments, such as in the BIOS or before loading Windows. However, I don't have any graphical issues in Windows.
Graphics card is a GeForce 8800 GT, on a MSI P35 Neo motherboard model MS-7360.
Edit:
Seems the capacitors on the card are bulging. I managed to fix my TV on my own by replacing them (repairman wanted $100!), and I might try doing this on my graphics card. It's a long shot, but I might be able to do this and see if this is the problem.
Best Answer
Its your GPU. Its not the exact same issue but its a minor miracle your GPU still works.
Basically nearly everything in the 8xxx family was flawed and tended to fail due to issues with the BGA soldering on the video card.
These issues could manifest themselves in many different ways - dell put out a recall on laptop GPUs with the same chip family and I've personally had failures of a 8300 and a 8800. Text mode wierdness is more common - like the famous image, but I'm guessing that your pre-boot drive practitioner runs in that mode.
Bob pointed out its a G92
And... its also apparently buggy
You should consider planning to get a new video card.