Good evening my name is ***** ***** I will assist with your query today.
Are you sure this is a BIOS password ***** not a hard disk password?
It does look like the BIOS password, however you do get some other POST screen like this. To confirm is this a laptop you previously had access to, and therefore know it doesnt have hard disk encryption enabled?
With regard to the B500 reset did you do this 3 times, first without RAM for 5 minutes, then for a further minutes with RAM in slot one, then again for a minute with RAM in slot 2?
This is 100% BIOS then, I think you have corrupted the CMOS.
Look at the video here (watch from 3.12 onwards).
The last thing you can do is remove the button cell on the motherboard, remove the battery and AC power, hold down the power button for 1 mintues, then try and start the machine up with the button cell and main battery disconnected, and just using AC power.
If this still doesnt work, the only option remaining is to replace the motherboard, you can buy new ones from ebay for around £40.
Sorry for the delay yes the issue is to do with CMOS, removing the battery is the next (more advanced) step than jumpering \ shorting the B500 terminals.
A new board can be found here.
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