Screen randomly blank, system responsive, backlight on

Maybe this is something simple...or maybe that's wishful thinking.

Toshiba A135-S4407 notebook. The screen will randomly go black, with the TFT back-light still on, only when on battery power, but absolutely nothing else is affected. I have been listening to music when it happens, the music doesn't skip, system is still 100% responsive and unaffected. Closing the screen, pressing buttons, clicking/moving the mouse/touch pad doesn't do a thing. When on battery power, I have the power button configured to go into standby/sleep when pressed, this is the only thing that works to bring it right back, press that, the system nearly instantly goes to sleep as normal, and then click again, comes back to life, screen pops right on. It tends to happen about twice through one cycle usage of the battery, so, once every 45 mins or so.

Possibly applicable video/graphics information:

Intel(R) Graphics Media Accelerator Driver for Mobile Report

Report Date: 10/12/2009
Report Time[hr:mm:ss]: 09:59:32
Driver Version: 7.14.10.1437
Operating System: Windows Vista (TM) Home Premium* , Service Pack 2 (6.0.6002)
Default Language: English
DirectX* Version: 10.0
Physical Memory: 2037 MB
Minimum Graphics Memory: 8 MB
Maximum Graphics Memory: 256 MB
Graphics Memory in Use: 68 MB
Processor: x86 family 6 Model 14 Stepping 12
Processor Speed: 1729 MHZ
Vendor ID: 8086
Device ID: 27A2
Device Revision: 03


* Accelerator Information *

Accelerator in Use: Mobile Intel(R) 945 Express Chipset Family
Video BIOS: 1377
Current Graphics Mode: 1280 by 800 True Color (59 Hz)



* Devices Connected to the Graphics Accelerator *


Active Notebook Displays: 1


* Notebook *

Monitor Name: Generic PnP Monitor
Display Type: Digital
Gamma Value: 2.20
DDC2 Protocol: Supported
Maximum Image Size: Horizontal: Not Available
Vertical: Not Available
Monitor Supported Modes:
1280 by 800 (60 Hz)
Display Power Management Support:
Standby Mode: Not Supported
Suspend Mode: Not Supported
Active Off Mode: Not Supported