This is the last straw for my computer, it finally froze again and refuses to boot windows xp.
It will do one of the following:
Boots, in the middle of XP loading screen blue screens for a split second, then restarts.
Turn on, radeon 4890 fan goes from 100% speed to 50% and hangs there, no picture.
Turn on, radeon 4890 fan 100% w/ red lights on back, and can't shut down without pulling the plug.
It used to do this and I solved the problem by moving RAM stick #2 to the 3rd RAM slot essentially making it 4GB single channel instead of 4GB dual channel. Now that doesn't work and I can't even use my computer.
btw, motherboard is a $50 elitegroup mobo and I am using 2GBx2GB DDR2 800 G.skill RAM
Also, I am not 100% convinced this is a motherboard problem. Red lights flashing on the back of a 4890 are usually to indicate the card is not getting enough power. Which could indicate a failing power supply, or simply that one of the cables is not plugged in or is loose. What kind of PSU do you have, and how old is the machine? The rest of the symptoms also seem to be in line with a power supply on the fritz.
If you have (or can borrow) another power supply, I would try that first.
The RAM trick you were able to pull also makes me wonder if it's not the PSU, then is one of the RAM sticks going bad. Have you tried booting up with only one stick of RAM at a time installed? Obviously you can't run diagnostics if you can't boot, but if one of the sticks is dead, that's a good way to weed it out.