Flickering screen when using Google Chat

[Hazarrd]

I'm having a strange problem. It's one that I've had previously (1-2 years ago) on my Thinkpad, but a different model (X61 I believe) and different OS (Vista). This problem does not always occur, and I haven't been able to pick out a pattern that explains when it occurs.

The problem (when it occurs): When using Google Chat within Google's web interface (www.gmail.com), the screen will "flicker" every time a new chat response is received (from my friend) or a new chat response is sent (by me). This does not happen if I'm viewing a different tab in Firefox, or if the entire browser is minimized.

I have the most recent drivers for all devices, including the display adapter.

I'm pretty sure I figured out a "fix" for this last time it happened, but I can't remember and Google search has turned up nothing (maybe I'm not using the right terms).

Any ideas on this?