Garbled Screen after sitting Idle

[M-88]

I'm running Ubuntu Netbook Remix 9.04 on a 16GB SDHC card Acer Aspire One D150.

The problem I have is if I let the system sit for 2-3 hours without doing anything on it, when I come back to the machine or move the mouse to turn on the screen, I get a small strip about 1/3 the size of the monitor going across.

I can run it all day and not have problems, but if I leave it for a few hours on its own it comes up the garbled screen.

I tried doing CTRL ALT F2 -F7 to get in command line and that doesn't seem to do anything.

Any suggestions as to what is going on here?

TYIA
M-88

[Haarlem]

Have you tried the latest drivers?