Please uncheck GPU acceleration under Edit>Preferences>Performance tab and restart lightroom.
Please let us know if it helps.
Thanks for you reply.
I tried that earlier and it crashes when I try unchecking that box aswell...
Are you in library module while changing the preferences or in develop module?
Make sure you should be in Library module.
If you still have problem doing it then please try the following steps:
1. Open the RUN window, type devmgmt.msc, and click ok, it will open the device manager dialog box
2. Select display adapter from the device list and expand it
3 .Right click on your Graphic card and disable it and keep the device manager window open.
4.Launch Lightroom and try to uncheck the GPU acceleration and restart lightroom
5. From the device manager windows , please enable the graphic card again.
Let us know if its of any help.
I found a solution, did some stuff in the AMD catalyst control panel, found it another thread=)
If it crashes again I'll try your idea, thanks for your help=)