770ED LCD problem: blank when undocked, but fine when docked

[Topslakr]

Are there any 770 users still out there?

I went crazy a few weeks ago and bought not only a Thinkpad 770ED but every accessory I could get my grubby little hands on. I have the port replicator, the Selectadock III as well as several options for the ultrabay and a myriad of odds and ends. Generally speaking, the laptop works great. Beyond installing the IBM listed 'maximum' RAM I've not attempted any sort of upgrades. After installing a series of OSes on the machine, I've settled on Windows 2000 which seems to offer me the best combination of speed and compatibly with other networked machines.

The only problem I'm running into is that LCD back light being somewhat finicky. Generally speaking, the LCD works flawlessly when the unit is docked in either the Selectabase 770 or the Selectadock III but when the unit is not in a dock, the LCD works only on very rare occasions. Obviously, I can plug a VGA cable into the back and use an external monitor but I'd like to figure out why the built in LCD works well in the docks, but not when it's undocked. The unit has no battery power to speak of, the meter just shows 0% which is not surprise, so in all cases the unit is plugged in via a wall adapter. The SelectABase 770 uses the normal laptop power brick and the SelectaDock III uses just a regular computer power cable.

I thought perhaps if I didn't 'undock' the machine in Windows it would confuse the display when undocked but that seemed to have no effect. There is a hot key to cycle the onboard LCD, an external monitor or both and while out of the dock I can see with a flashlight that the display is working, the backlight will no turn on no matter what I do.

Any ideas?

[Mod edit: moved from Official Upgrade thread.]