thinkpad t40 wont show display.

[Warrior 3000]

so i have this IBM thinkpad t40. when ever i turn it on the lights go on to show its on and all but the screen is just blank and nothing happens. idk what to do or how to fix this. please help. i did all the Fn and f keys toggether and i get nothing. i know for sure its booting up cause the light comes on and everything. i just put a flash light tot he screen and didnt see anything.

[ajkula66]

Welcome to the forum!

Can you hook it up to an external monitor and see whether it displays anything on it?

[Warrior 3000]

no i cannot see anything on an external monitor.

[rkawakami]

Just to be clear, if you connect an external monitor after the system is turned on, then you will need to do an Fn+F7 combination in order to activate the external VGA port. One problem with that is if you have Presentation Director installed it may pop up a window (which you can't see) giving you some choices to click on. And this assumes that you don't have any Windows login to deal with. Possibly the best thing you can do is this:

- with the system off, connect a monitor to the external VGA port and turn the monitor on
- power up the system and in about two seconds press the F1 key several times (to get into the BIOS)
- give the system a few more seconds to get into the BIOS menu and then press the Fn+F7 key combination

That should enable the external video. If you still don't see anything, then you probably have a loose GPU. Fixing that generally requires a solder re-flow, although some people have had some limited success with putting pressure on top of the GPU (wedging paper or cardboard between the keyboard and graphics chip).

[Warrior 3000]

it wont work the an external monitor. so whats wrong with the laptop and what do i need to do to fix it.

[rkawakami]

From your described symptoms of no video (LCD and external), the fact that we're talking about a T40 system and the assumption that the system was working properly for you before, then the best guess is that the ATI graphics chip (GPU) has come loose from the motherboard. This can be verified by putting some pressure on top of the GPU and then booting the system. If you then see (mostly) normal video, then that's a good indication that some of the solder bonds have broken underneath that part. There's typically four ways you can deal with this:

- replace the motherboard
- keep something wedged between the GPU and keyboard
- attempt to perform a solder reflow using a heat gun and plenty of luck
- have the motherboard professionally reflowed