Graphic card issue when using a 2nd monitor

[walk]

Ok so here's the relevant specs first -

2.4 GHz MacBook Pro
4GB Ram
GeForce 8600M GT
OS 10.5.8 with Windows 7 Ultimate on Bootcamp

I've been using the above MBP with an LG-32LB75 TV as a 2nd monitor via a DVI to HDMI cable. I've never had any problems with this on either of the operating systems, it always just worked without any setup. Until a few days ago - all I now get on the TV is a 'no signal' message. I'm 99.9% certain that the issue isn't with the TV itself as I've since had it working as a 2nd monitor on an old PC and it was fine. It's also not the cable as I've tried two different ones and they both worked with the old pc but not with the MBP.

Both OSX and Win7 seem to be receiving some information from the TV as they they can recognize the TV model and I can move the mouse off the side of the 1st screen as if the TV was working fine. This problem seem to only be applicable when connecting to the TV as I've been able to use on old dell monitor as a 2nd screen without any issue. Has anybody had any similar problems? I'm really stumped and I'd really appreciate any help or suggestions.

Thanks in advance

 

[dap1215]

I had the same issue and within a short period of time my logic board died and I had to have apple replace it.

You might find this apple article helpful:

http://support.apple.com/kb/TS2377

I feel for ya!

Good luck!

 

[cluthz]

I had same issues with external screen.
I did a hardware test and got an error on graphics card.
Then I called apple and made an appointment with my local apple store which replaced my logic board within a few hours.

After that, no problems!