The Standard VGA driver doesn't provide full functionality.
The drivers that I can download from Lenovo or what Windows Update installs cause crashes while running on battery power.
I tried wiping all traces of those drivers using Driver Fusion and downloading fresh drivers but they still cause crashes.
This may be an issue for Lenovo, but this machine is well past the warranty period.
What to do?
I have changed the windows update setting so I can be sure the Standard VGA driver stays put.
Standard VGA is only meant as an installer placeholder driver until optional Updates delivers a newer driver, or you provide it yourself.
You may need the Intel chipset drivers in this case to help identify correctly your Intel Display chip: Intel Chipset Device Software for Windows Vista and XP - ThinkPad SL300, SL400 and SL500
If that fails I would manually identify beyond doubt the exact model display device to find and try the driver from the manufacturer's Support Downloads webpage: Hardware Identification.
In rare cases where old hardware is failing to find a driver, I use DriverMax for it's 3 free drivers per day. It isn't much needed with Win7 but is more accurate than any other driver program for finding difficult drivers.
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