X server graphics problem on slackware 12.0
 

I installed slackware 12.0 on a toshiba satellite A10 and when I run Gnome or KDE for first time everthing works perfectly fine. When the screen goes into sleep mode and then back to normal mode it seems that the 3d accelerator is not working. the graphics card is an intel i850 i think. I tried ctrl+alt+backsp to stop the x server and then back again startx and it still doesn't work.

any ideas?

Thanks