System specs:
OS X Leopard 10.5.7
2006 24in Imac
Nvidia GEFORCE 7600 GT

I wanted to try out an open source vector drawing program and downloaded Inkscape earlier today. I already had X11 installed. When I tried to launch the program the Inkscape and X11 icons appeard in the dock but nothing else happened.

While I was waiting during the events above I switched to Adobe Lightroom (which I already had open) and after using the program's 'lights off' feature a grey 'screen' appeared over the entire screen, with all graphics becoming washed out.

This is NOT the X11 'full screen' preference problem. I tried restarting, resetting PRAM, updating to OS X 10.5.7 (I was running 10.5.6 when the above happened), fixing permissions, booting into Windows through bootcamp and doing an Apple hardware test. The screen 'grey screen washout' problem remains in all these scenarios (during the grey apple startup screen, in the OS X user log in screen, in Windows bootcamp, in the apple hardware test screen, etc.)

I suspect me using X11 at the time of the problem may be a coincidence and the video card has a problem, though it would be quite a coincidence… The Apple hardware test said all is okay, but under 'Videocard' it said 'unknown video' or something similar. Could X11/Quartz/similar stuff affect the video card's firmware or the system's .kext files, thus affecting the video like this?

I've uploaded a log file (104kb) I saved from the OS X Console utility here (search for 'Lightroom' in the file for the approximate time the problem happened): http://hypertexthero.com/ConsoleMessages.log

Any help much appreciated—especially an answer as to whether X11 could affect the video card in this way. Also, any way to 'Flash' the videocard's firmware?

Cheers,
Simon