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hasco
14-07-2003, 03:59 PM
A few posters lately have talked about flashing the bios.
What does this mean exactly?(but keep it clean ;-)
Cheers
Rick

godfather
14-07-2003, 04:18 PM
Reprogramming the Basic Input Output System chip on the motherboard.

Only needed if you are trying to install equipment not supported by your motherboard when it was programmed originally.

Can be required if a bug has been identified in the present system also.

Other than that its not a required event, it has the real potential to make the motherboard unusable if it goes wrong.

Graham L
14-07-2003, 06:10 PM
Yep. Definitely a case of "don't fix if not broken".

The "flash" refers to the technology, not the style of overcoat you have. The BIOS and raw boot code is stored in read-only-memory. This used to be magnetic memory (I once rewired two words of a PDP8 boot ROM) , then masked ROM (programmed once in the chip factory), then for a long time EPROM -- ultraviolet erasible programmable rom -- (sometimes EPROMs without the quartz window for lower cost). Now, they use flash memory, which can be erased and rewritten, purely electrically, in place.

Basically, you download a package containing the new code and a programme which does the deed. You put these onto a bootable floppy (or, I suppose, a CD these days), boot to DOS and run the programme. It saves a copy of the present contents (non-destructive, so far :D). Then it writes the new code. If the power goes off halfway through, you might be lucky. There may be a non-changeable section which will let you boot again and have another go. There might not be. :_|

But like any major operation (it's like replacing the legs of a ladder you are standing on) there is scope for disaster. Murphy's laws having no exceptions, it's a very good idea to rewrite a BIOS only if it's essential. It's usually only "desirable" if the motherboard worked when it left the factory. :D

parry
14-07-2003, 07:09 PM
Hi, agree with all the comments above. As an example of why you may need to flash a BIOS, I recently installed an 80GB drive and my existing BIOS would not recognise it. It seems the size limit was exceeded but luckily the manufacturer had a firmware update (the software you run to flash the BIOS) so I could use the drive on my PC. It was definitely cross everything and hope a power cut doesnt happen in the middle of the operation!

If you ever need to do this make sure you get the right details of your motherboard and download the correct firmware or else your likely to end up with an expensive paperweight.