My T40 2373-72U started having boot up and freezing problems about a week ago. When it froze, I had to hold down the power button to force the system off. One time the screen did this purple and green flashing thing, followed by grayish on the top half and black on the bottom half of the screen, and locked up. After that, it wouldn't boot up at all. No hard drive activity, no fan, no IBM splash screen, nothing but the power indicator (running on AC only).
I took most of the system apart, reseated everything I could find (HD, main DIMM, expansion DIMM, LAN card), pushed down on the GPU, and reassembled.
I thought I was golden! The system ran for three days. Then the purple/green and gray/black screen happened again. Now it won't boot at all, even with a full 24 hours to cool it down (if there were a possible heat problem).
I haven't followed the numerous GPU threads over the years, but my guess is that the GPU is dying (or dead) and that this is a VERY BAD THING. I have the ATI 7500 GPU.
I LOVE this machine. Just breaks my heart to think that it might be dead or that it would be ridiculously expensive to fix. Of course, over the years, I've upgraded the RAM, the hard drive, and replaced the broken keyboard and system fan. But it's just such a GREAT laptop! It has been my workhorse for years.
I lay myself at the mercy of your speculations and suggestions with a tear in my eye.
W520 4276-38U (NVIDIA Quadro 1000M Optimus, 15.6" HD+, i7-2720QM, 8GB RAM, 500GB HDD, Win7 Pro)
T40 2373-72U still going strong after nine years and a near complete restoration with repairs and upgrades
I can't imagine owning anything but a ThinkPad, thanks to the gurus of this forum!