X-server crash?

[yotestalker]

Hi,

Recently, whenever I launched a video with totem, my screen would go 
black and I'd end up back at the FC17 login screen. I was using the 
akmod-nvidia and kmod-nvidia drivers. I switched over to VLC as my 
default video player and the problem seemed to be solved; however, It's 
now doing the same thing whenever I try to launch google chrome. The 
screen goes black and I end up back at the login screen. It does it in 
both KDE and XFCE. Has anybody else seen this?