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The lack of any sound when the AC adapter is plugged in might mean that the BIOS has been told not to issue the "Power Control Beep". This option is available under the Config/Alarm section. Note however, that the speakers may simply be muted (press the volume up button a couple of times and see if you get any sounds). Of course, if you can't see anything on the LCD or external monitor then how can you navigate to the proper BIOS menu??? If you want to try to toggle this setting blindly, then:
- press the power button to start up the system
- within 5 seconds, press and hold the F1 key for at least two seconds
- press the ENTER key once
- press the DOWN arrow key 10 times, then press ENTER
- press the ENTER key, then the DOWN arrow key, then the ENTER key once more
- press the ESC key TWICE
- press the F10 key, then the ENTER key
This entire procedure will toggle the power control alarm setting. If it was disabled, then this should enable it. If you then get beeps when you attach and remove the AC adapter, then at least you have proven that the BIOS is working.
I'm assuming you have either attached the external monitor and have it powered up prior to booting the T41 or you have tried pressing the Fn+F7 key combinations a couple of times, once the system has been running for several seconds. If so, then the lack of video in both
the LCD and external monitor probably means a motherboard issue (sorry
). If only the LCD was not working but external video was fine, then that might point to a bad inverter, CCFL (the backlight inside the panel), a bad ribbon cable or a stuck lid switch.