TC4400 Screen turns white, system still responds

I have a TC4400 that has been very reliable until just recently. When I'm plugged in, I have no issues with it whatsoever. When I'm running on battery, however, the screen does some weird stuff.

At first, I thought it might have been the program I was using (ArtRage Stuido Pro) that was putting some kind of strain on the system. However, it's started happening in other applications, too.

The screen will flicker occasionally. That is, everything seems to jump to the left for a few hundredths of a second before snapping back to where it belongs. Almost like a power surge will affect a monitor. After an hour or so, the screen just goes completely white. No cursor, no anything. The system, however, doesn't lock up. I'm still able to ctrl+s to save whatever I was in then win+r and issue a manual reboot command.

Like I said, everything works fine when it's plugged in. I never see the flicker nor does the screen blank. I searched the forum for a similar issue, but the only flickers people mentioned had to deal with the screen dimming, which mine never does. And none mention the screen going completely white.

I'm using Windows 7 32-bit, have 2x 1GB memory modules installed, and replaced the HD with an SSD.

Has anyone experienced this? Or does anyone have any suggestions for how to approach it?