Thanks for the advice everyone. I will try dumping it again tonight as if it were a 28-pin 27c256:

All these variants of the 28-pin!

^ better try as 27C512 and see if you get duplicate data (2x32kb data)

In my experience, almost all 386 BIOSes that use a single chip are the 512kbit variety.

And 256kbit was largely for VGA ROM's?

yup

Just dropping these two MR BIOS manuals here, I harvested them from the eSolutions web site; still poking and trying to find a way to get to the BIOS files 😎

I have a board from 1991 with the MR BIOS on it, would anyone wager a guess as to what the HDD size limitation would be? I'll get a CF card of the according size. I'm thinking of playing it safe and going with 512MB which should be plenty enough for a DX2-66.. But if I can get away with 1 or 2GB, why not?

I have a generic VLB board with a SiS 85C471 chip set . Can anyone say with certainty which of the indexed BIOSes fetaure that chip set?

Thanks for your replies.

-CH-

512 MB ok for your DX2-66 system? I need at least 2 GB. I use SCSI so the onboard BIOS limit is unimportant.

appiah4 wrote:

I am going to build a system with this board sometime in the near future, I will try to dump the bios with uniflash.. […]
Show full quote

I am going to build a system with this board sometime in the near future, I will try to dump the bios with uniflash..

For now, please see attached the copies I found of the latest and large HDD patched Mr BIOS bioses.

This board is supposedly based on Headland HT 340 "SHASTA" or possibly Opti 82C802G . Can you confirm which?

and why use uniflash for this? if the board runs then NSSI is better to make a BIOS dump

Do you know what the benefits of NSSI copying a BIOS is compared to Uniflash?

not having to remove the IC and inserting it to a NIC to do the job?

Doesn't uniflash work with most PC BIOSes in the computer?

Anonymous Coward wrote:

appiah4 wrote:

I am going to build a system with this board sometime in the near future, I will try to dump the bios with uniflash.. […]
Show full quote

I am going to build a system with this board sometime in the near future, I will try to dump the bios with uniflash..

For now, please see attached the copies I found of the latest and large HDD patched Mr BIOS bioses.

This board is supposedly based on Headland HT 340 "SHASTA" or possibly Opti 82C802G . Can you confirm which?

It has the Headland chipset.

Were there other 486 boards that used the HT340 chipset? Do they work with EDRAM as well?

Anonymous Coward wrote:

Were there other 486 boards that used the HT340 chipset? Do they work with EDRAM as well?

This I do not know I only have experience with this one board.

Here's the correct binary for the Forex 300 MR BIOS as a 27C512 (64kB as opposed to the 16kB)

Just recently I got several other motherboards so I ordered a USB programmer.

Motherboard photo:
download/file.php?id=42321&mode=view

thanks for the update Auzner - I'll fix my post with the new dump 😀

I think I finally tracked down the BIOS image for Macronix 305/306. It's for the Octek Jaguar V. It came from a Russian Hardware Museum site.

http://hwmuseum.pp.ua/index.php?route=hardware&dev=3

I think this image is actually floating around as an attachment on vogons somewhere, but it hasn't been added yet.

thanks Anonymous Coward , added the BIOS image in the 2nd post list