T61 Screen Flashing & Shutting Down

T61 Screen Flashing & Shutting Down: Graphics Card, nv4_disp Error, and/or Monitor Cable Problem?

Hey there gang. I am having a pretty significant problem with my T61 and believe I've got it narrowed down somewhat. I'm not very knowledgable about PC repair or anything technical, so I may be way off and/or wrongly describe my problems by using incorrect terminology.

I need your help!

I'm going to try to be as thorough as I can in my description, but the post title is a good overview of my problem.

Recently, my T61's screen has begun to flash intermitently. The problem tends to resolve itself after a day or two of not using the computer. Usually - but not always - this happens after I take my laptop somewhere and it rides in my bag. I will start up Windows XP and the screen will flash from black to displaying my desktop. Two things happen then:

1. If the PC has sucessfully started up and I'm at my desktop, I'll get a logoff screen that says Windows is going into Stand By, and the computer powers down, or
2. If the PC hasn't fully booted up, it just appears to reboot and goes into a cycle until I forcefully power off by holding down on the power button.​

I have a friend who used to do computer repair who opened up the back and looked at the problem. Her initial suggestion was that the monitor cable / one of its pins was loose and the pin just needed to get reseated.

She was able to press down on the plastic covering the cable to prevent the screen flash. The screen flashing was also avoided when she plugged it into an external flat screen monitor. However, when I got home, I was unable to duplicate either of those "fixes." I borrowed a friend's CRT monitor and plugged it into my ThinkPad T61 and am still having the screen flashing problem.

The problem took a turn two days ago when I tried to start up the T61. It flickered as usual and I manually forced a power down. When I tried to start it up again, i got a " nv4_disp" error and the user login screen came up (never happens as I'm the only user) looking like the number of colors were way restricted (like a gif with only 32/64 colors sort of thing). This was a new problem I've seen.

Could this inidcate my whole graphics card is going south and its not just the cable? Or both the graphics card AND the cable? Or it's just a drivers problems?

My friend's reply was: "It could certainly be further indications of cable problems, but that kind of escalation coupled with actually errors probably means something else is wrong too. The graphics card is a good bet, most likely not driver issues. Screen flashing and crashing usually means hardware, not software."

So, here's where the rubber meets the road. What do I do here?

The monitor cable is just about $25 from Lenovo, but would that be causing the system to be shutting down, too? And where does this nv4_disp error factor in?

If it's the graphics card, how much is that going to cost to replace?

Thanks in advance for your help - I'm over my head here.