Help! Dell C840 no display and shut off after 3 secs!!

[canary3547]

Hi there,

Tried the 24C02 shorting trick to reset the BIOS password. After I tried a few times. Even when I did not short the chip, after i switched on, there is no display and the notebook shut down itself after 3 seconds. WHat's going on? I am panic now! Please help! Thanks.

 

[Paragon33]

It sounds like you may have grounded the Pin #8 which is the voltage feed to the chip, or else the board had problems that did not show because of the password stopping the the boot. I cleared the password on a C610 Tuesday this week and found the board had serious problems after the password was gone. I replaced the board, but that one I had bought first was no bargain.
You can try removing the Keyboard and unplugging the Palmrest connector; that also disconnects the CMOS battery from the board on that model. Leave it disconnected for a while and then reassemble the laptop. See if resetting CMOS will do any good. Also, check your RAM and CPU for seating and also the RAM and slots for operation by trying first one and then the other Module in both slots, to identify a bad Module or slot. The cpu pins are very short and it does not take much miiseating to render it inoperative.