I looked thru the Way Back machine and got BIOS for two BX Slot-1 but they are all 1Mb roms. What exact models are the boards ?

Thanks Horun for your reply

The one i'm trying to save now is a Freetech P6F91i.
I've just been able to find a BIOS file...maybe it's not the right one...
I'm trying to Flash the 2MB version of this BIOS (as my EPPROM is 2Mb), but after each flash i get the same error message : Bios ROM Checksum error and the board is booting on the floppy. Can't understand what's goig wrong ! 😒

Can you post whole pictures of motherboards with replaced resonators? Bios ROM Checksum error could mean that BIOS you are trying to flash is incompatible with motherboard (but it's compatible enough to display something).

I posted the BIOS files and Manual for the P6F91i in Vogons Driver library:
http://www.vogonsdrivers.com/index.php?catid=1&menustate=0,0

I'm not on Windows at the moment but as I recall, this is how you double up an image file:

copy /b infile.bin+infile.bin outfile.bin
Don't forget the "/b"

If I'm doing that right then outfile.bin will be 2 copies of the infile appended to itself. This has the effect of disabling the upper address bit, by making the chip return the same data no matter what the upper bit's value is.

Thanks all for your help 😀

I tried with Horun provided BIOS and result is the same : the flash process is OK and then, when rebooting the board, same message "BIOS ROM Checksum error" and the board boots on the floppy...
Another strange thing with this board (maybe crystal related), is that i can't power it down using the corresponding pins off the front panel. The board is powering on automatically once started and if i keep the pins shorted for 4s the board power down then up...

I will post pictures of the boards later this day.

Hello Shamino ! Happy to see you here !

The command you give is the good one, i'm able to create a 256Kb file with the same two 128Kb BIOS.
When trying to flash the program is displaying a Cheksum code then the computer lock.

I'm turning crazy with thoses flashes 😁 i think i'm missing something...

parhelia512 wrote:

The command you give is the good one, i'm able to create a 256Kb file with the same two 128Kb BIOS.

Ok. The pin 30 of EEPROM is A17 for 2MBit-chip and NC for 1Mbit-chip.
So check pin 30 of EEPROM dip32 socket (extract chip from there carefully before)
If it is connected to GND - BIOS should work. Otherwise isolate a pin 30 of BIOS chip from the socket pin and connect the pin 30 of BIOS chip to GND.
(I don't know how to say it in English clearly - Just bend out pin 30 of BIOS chip to lose contact with socket pin 30)
Now A17 will be in low level.
Make it only on your own risk.

Thanks Roman555

If i understand correctly, if i isolate the pin 30 on the BIOS chip, it will act as a 1MB one ?

Have to ask a few Q based on the pictures you posted on 11/30 and general BIOS stuff: forgive me if these seem simple but maybe you missed something. Did you install good a battery ? After flashing BIOS did you enter BIOS and load BIOS defaults, save and reboot ?
The picture is not very clear but appears that the CMOS/RTC IC is right near the battery and AGP slot, is there any damage to traces ?
Can you take a better picture in that area ?

Hello Horun 😀

I tried without battery and with battery and same results.
I can't enter BIOS in both cases. I use the CLEARCMOS jumper after BIOS Hotflash and i stop the Hotflash computer before it reboots.
For the BX : i have AWARD Recovery starting each time i boot the board with checksum error...can it be crystal related ?
For the VIA : i only have the Video BIOS displaying and a blinking cursor : The computer seems locked : can't reboot with CTRL + ALT + DEL. Once (i can't remember if it was with or without the crystal installed) the Board loaded the POST screen and locked. But i can't reproduce the behaviour. Only the Video BIOS displaying.

I will try to do better pictures this weekend.

oh boy theres lots of bios for that board on this site.
http://www.tacktech.com/bios.cfm

This guy here had your same problem
http://www.motherboards.org/forums/viewtopic.php?t=23625

parhelia512 wrote:

Thanks Roman555
If i understand correctly, if i isolate the pin 30 on the BIOS chip, it will act as a 1MB one ?

No, the pin 30 of the eeprom has to be isolated from the socket and connected to GND. Of course, it has to be programmed before with that doubled bios image. But working part of image will be low addressed one.
If you have proper 2Mbit bios image for your mainboard you shouldn't do that.

P.S. if P6F91 could be supplied with both 1Mbit and 2Mbit EEPROM it means there is a factory jumper to configure that. So pay attention to pads designated JP1 near eeprom socket - it might be answer. I think it's easy to understand which model of eeprom the motherboard has to use. If A17 of eeprom socket is connected to A17 of address bus - it should be 2Mbit EEPROM. The A17 of address bus is pin A14 of ISA slot.

P.P.S parhelia512, did I get it right that you program eeproms using a hotswap method ? Do you flash BIOSes including BootBlock ? (I mean, sometimes tools program only main part of BIOS)

Waouh !!!

OK, things are a little more clear for me...if the board is reading the EEPROM as a 1MB one, it's normal that i run into BIOS error.
Do you think that changing this jumper position (can i short the pads ?) can make the board runs with a 2MB EEPROM or is there another difference on the board physical configuration that explain the 1MB or 2MB EEPROM choice ?

Thanks Roman555 for all this insteresting details ! 😀

I actually don't think there is a problem with your board, I think you flashed the wrong bio for it and now it will not accept a differnt one. A better approach would be to remove the bios from the board and use an eeprom flasher until you figured out the right bios. 🤣 I think all of these fixes are based on the board being faulty which I am not convinced of, all of the evidence leads to a software and programming failure.

parhelia512 wrote:

Do you think that changing this jumper position (can i short the pads ?) can make the board runs with a 2MB EEPROM or is there another difference on the board physical configuration that explain the 1MB or 2MB EEPROM choice ?

I've thought a little bit. Factory jumper isn't necessary for that. The pads JP1 might be just "bootblock protection" for Intel flash 28F001 - its pin 30 is for that. So just try to understand whether the A17 of eeprom socket is connected or not to A17 of address bus. If it is yes then 2mbit eeprom should work just out of the box.

Warlord wrote:

I actually don't think there is a problem with your board, I think you flashed the wrong bio for it and now it will not accept a differnt one. A better approach would be to remove the bios from the board and use an eeprom flasher until you figured out the right bios. 🤣 I think all of these fixes are based on the board being faulty which I am not convinced of, all of the evidence leads to a software and programming failure.

Yes, I agree, It might be too.
parhelia512, although you didn't answer how you program the eeprom, what software utils you use.

Yes, the BIOS was flashed using hotswap method. I flashed with "success" using the /Wb option that should write the Bootblock.

I tried using UNIFLASH but the flash process was not OK, so i'm now using the AWARD flash utility version 860b if i remember correctly.

Thanks, so bootblock should be Ok!

a physical device like this https://www.youtube.com/watch?v=xp5kPobFCLg