I have been looking at this Toshiba Satellite C650 BIOS on and off for a while, this is NOT a 4 mbyte bios "Pro" version. The actual product number is PSC08C-01V019. Since the Dynabook link isn't working for the BIOS, I FTP'd it up to
http://www.meckanic.com/BIOS_PSC08C_PSC09C_170_WIN.EXE and it is an original from Toshiba from a few years ago. The actual BIOS file name is mu10m170.fd and is only about 1 mbyte long (1,048,576 bytes). All of the text appears to be soft encrypted as there are only 3 words in ASCII, two of which are TEXT.
The computer has a rather cheezy little T4500 cpu, I have a T9400 kicking around here and would like to give it a shot in the wee beastie, but there is no auto-config for changes in processors, unless of course it's hidden. I have tried things like A+F10, A+esc, A+del, A+F2, etc., but nothing gets me into any advanced menu. I do have a CH341A and 8 pin clip, so I can re-program the BIOS on the motherboard if I have to. I have done quite a few on-the-board, especially fixing those fake video cards from China, bringing them back to proper GTX-550Ti's.
Maybe you are able to unlock the advanced features?
It is Insyde 3.5 BIOS BTW, you just can't see it in the pics.
Thanks & Cheers - Dave