It overheats, needs more memory, cd tray (I think) wasn't there and several other things he needed doing. At present it is with a computer expert - and I am very surprised he is having trouble as he is quite a genius - and he has asked what is the BIOS password. I don't know exactly why he needs it.
If someone was repairing my computer and asked me for my password I would not be alarmed because he would not want to reset my password, if I then told him I dıd not know it and I was then informed he did not know how to reset it I would be worried.
If he does not know how to reset it, then if he is indeed an expert then he is probably an expert in another field because he certainly isn't one in computer repair.
As an aside upgrades should not need to be done through Bios unless something has been disabled, if he has added something and the computer has not had bios altered and it does not see the upgrade then I suspect your guy has not done the upgrade correctly.
The motherboard will have a jumper switch to clear the bios to standard settings or just remove the battery as has already been stated (without it being plugged into the mains) and it will clear.
If it is a desktop PC then it will be easy to get into but if a laptop the case may need splitting and that is not normally for the faint of heart therefore he should download a reset program and run that to clear it.
Send him here to download a program that should work
CmosPwd - Free tools and utilities
If he reads the instructions and knows about admin privileges and services he should be OK if not then I can not really comment on his abilities as he may be a friend of yours.