drgigabyt
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BIOS Password reset for HP/Compaq Presario 2100
Has anybody been sucessful in resetting a BIOS / Supervisor password on a Presario 2100 (Model 2135US)? I got it used and took a gamble on being able to reset the pwd, but after ripping it apart, removing CMOS battery, and putting the whole thing back together, it is still locked up with the password on boot. Can't access boot sequence to use a software utility either. Tried online chat with HP, that didnt help. The only thing left to do is take it to HP Service unless somebody out there has a fix. Thanks!
ASKER
I have tried all sorts of passwords, including Compaq, Presario, model #, etc, etc.. I've also attempted the kyeboard buffer overload trick, no luck. After talking with HP support and authorized service centers, it seems that Compaq did not provide any backdoor passwords or simple over-ride procedures. It appears that the only way to reset it is by removing the CMOS battery - which I've done - and THEN reprogramming the BIOS chip. I am not sure it's worth the pain; the CMOS battery is located on the underside of the motherboard, which requires complete disassembly of the laptop to get to.
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puter geek: No system is not under warranty. As it turns out, after removing the CMOS battery, the BIOS apparently goes into a default non-boot state that requires re-flashing. Since none of the built-in boot options (CD/Floppy) will work, you have to use a special LPT port 'jumper block' of sorts to enable an external Parrallel Port floppy boot with a FLASH bios floppy. I have not tried that so can't say whether it would work or not.
@drgigabyt--> where did you come across this info on the LPT port, and could you provide a bit more detail on how this is accomplished.
Here is the service manual for your laptop
http://h20000.www2.hp.com/bc/docs/support/UCR/SupportManual/TPM_319733-002_rev3_us/TPM_319733-002_rev3_us.pdf
On page 2-61 it gives the explanation on the boot block jumper under the heading-->Repairing the BIOS IC
http://h20000.www2.hp.com/bc/docs/support/UCR/SupportManual/TPM_319733-002_rev3_us/TPM_319733-002_rev3_us.pdf
On page 2-61 it gives the explanation on the boot block jumper under the heading-->Repairing the BIOS IC
This will only allow you to recover from a corrupt BIOS, but it won't do anything about the BIOS password. This password isn't stored in the BIOS CMOS, but rather in a security chip. The BIOS password, if forgotten or unknown, can only be reset by HP, usually a new mainboard is necessary. And they will only do that if they get proof of purchase.
Overloading the keyboard buffer smetimes will allow you into the bios. To do so just keep hitting the ESC key repeatedly during startup.
Other methods are pretty intrusive, and the possibility of the first 2 that I mentioned are low percentage to work.