4 mb flash bios rom, everything you need to know?

Hot-swapping and Boot-Block flash & Boot block flash and floppy support
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atang1
BIOS Newbie
Posts: 17
Joined: Sat Jan 01, 2005 7:18 pm
Location: Framingham, Ma.

Flash devices have a write life of 15,000 writes and then they die, That was the old rule. Flash was based on Dr Andy Groove of Intel's patent. His invention uses doped silicon dioxide to flow or anneal the stressed cmos gates. But, in shrink the dimensions to submicron rules, the annealing process has some ideosyncrocies,

Namely, aging effect was not known or fixed in semiconductor processing. So, as flash ages, it disfunctions. But if you warm it up, it will anneal and recover. You have to use flash often, or it will slow down.

It can slow down so much, that beep code can be triggered. But just by warming the motherboard and use it more often, it will recover and speed up to boot quicker. Especially, you will notice the boot logo goes away faster.

Good luck. Don't fix it if it ain't broke. Just like old electronics equipment, you need a time delay to warm up before you boot. Or warm up with error, and reboot later?

Footnote:
I know Dr. Groove personally when his then boss Dr. Robert Noyce introduced us.
atang1
BIOS Newbie
Posts: 17
Joined: Sat Jan 01, 2005 7:18 pm
Location: Framingham, Ma.

With the possibility of bios slowdown in posting, some motherboards may appear to be dead; if you did not use 133 mhz FSB cpu on the first try.

66mhz and 100 mhz cpus often can not post.

Resulting in mini post card stalled at 00, 88 or FF.

So, the first approach is to have 133 mhz sdram and cpu ready for your motherboard. This applies to most of the newer S370 socketed motherboards.

On p4 motherboards, 400 mhz FSB really is 100 mhz based(dual double data rate). If you use PC2100 DDR dimms, you will get 266 mhz FSB(single double data rate).

On P4 775 pin cpus, you have to use DDR2.

To run motherboards, you have to have cpu(frequency) that has the correct wait state in the bios(multiplier range to FSB), then memory is checked for first 640 kb to shadow the bios in ramdisk; after that your bios will look for HDD. If you don't have HDD connected, bios may stall at the cmos checksum, not having floppy or HDD. So, you look for sequential problems posted by your bios to get the motherboard going.

Good luck.
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