Weird Screen behavior...

[John Pariseau]

Up front: 550 mhz Ti, no Combo drive
10.2.6
Photoshop 7 with latest updates

This has happened before, twice today:

I take a layer, command+t (transform), rotate the layer, hit enter, and 
boom! My screen looks like I am taking a butter knife to the cable - 
thin horizontal lines appear, like TV static, and my screen jumps 
around.

Should I be concerned?

BTW - Classic is open, with Quark 4.11 open