BIOS Updates forum

Hi,

I've got a problem with Socket 370 Mobo. It has 256 kb ASD Bios chip
AE49F2008 (= Winbond W49F002U according to Uniflash table).
The mobo doesn't start or beep at all. Moreover, all fans start
working immediately after powering up.
I tried to reflash above chip on another mobo with Winbond W29C020C
(=ASD AE29F2008). Uniflash didn't recognize the chip at all.
Then I forced it to W49F002U and flashed: plenty of errors during
flashing. I read that many people had problems with flashing
AE49F2008=W49F002U. So my questions are:
1. What program to use to reflash this chip (if it is not corrupted) ?
2. What a difference between W49F002U and W29C020C ?
They both 256k, I read specification sheets and didn't see much
difference. I've got a spare W29C020C and don't know where
to get W49F002U. Are they replaceable ?
If yes, should I flash W29C020C with some other program (not
Uniflash) ?

Thank you.

There are problems with the W49F002U and UniFlash which might be fixed in next version. Try another flasher in the meantime.

1. What program to use to reflash this chip (if it is not corrupted) ?

If your original bios is award, use award flash version 7.72 for flashing W49F002U or W29C020C.

2. What a difference between W49F002U and W29C020C ?
They both 256k, I read specification sheets and didn't see much
difference. I've got a spare W29C020C and don't know where
to get W49F002U. Are they replaceable ?
If yes, should I flash W29C020C with some other program (not
Uniflash) ?

W49F002U has RESET pin and W29C020C doesn't have, all other things are the same. But it won't matter if the RESET pin is connected or not. I have tried this on my own board, and I didn't have any problems interchanging these 2 chips.

I usually use Amiflash or Gigabte Uniflash (based on Amiflash) to reflash a 49F002U .
Amiflash is able to work as universal flashprog with some small option changes such as bootblock write activated and clear CMOS disabled and some other small thing .
I usually have Aminf329 or 332 modified for this use

W29C020 is a small sector flash ROM - no erasing needed, each of the small sectors is auto-erased when programming, it's pretty fast
W49F002U is newer and uses big sectors and AMD-like commands (like most flash ROMs today), each sector must be erased before programming. Looks like some of these chips require longer delays or the programming will fail.

These chips are pin-compatible, so most probably you can replace W49F002U with W29C020. I think that it might not work correctly the other way - older BIOSes might not support W49F002U chips.