fuzzy horizontal strips on screen and freeze

[gwenn-ha-du]

hi,

since i have installed fedora 6 on an x_86/64 intel core duo 2 machine, i have had 2 problems.

1) at times i get 1 or 2 horizontal fuzzy strips spanning the entire width of the screen. i'll try to capture a snapshot next time
2) the system freezes completely. no mouse/keyboard response

although these two problems have happened at the same time, the first one has happened on its own w/o any application running.

where to begin to troubleshoot this problem?

thanks.