Are BIOS chips interchangeable?

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I have a few GPUs with probably defective BIOS chips. Since they are different and I would like to not have every single eeprom chip in existence in stock in case I need them some time I was curious how far interchangeability goes. Can I just use any SPI eeprom with enough capacity for the bios and the right pinout or do I need to watch out for something?
 

sc5mu93

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I have a few GPUs with probably defective BIOS chips. Since they are different and I would like to not have every single eeprom chip in existence in stock in case I need them some time I was curious how far interchangeability goes. Can I just use any SPI eeprom with enough capacity for the bios and the right pinout or do I need to watch out for something?
Can you not pull the make/model off the defective chip and order the exact same thing from mouser or something? Pretty sure techpowerup or the like includes most BIOS images for a lot of cards.
 
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Yes I can order the exact same chip but I would like to just keep one type in stock and use it for all card which need it. That's why I would like to know whether they are structurally similar enough to do that. :)
 

Dan_D

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I have a few GPUs with probably defective BIOS chips.
I'm not sure how you reached this conclusion. I've serviced PC's of every kind for over two decades. Literally 10's of thousands of systems and I've only seen a few GPU's, motherboards etc. with bad BIOS ROMs. I can probably count all types of BIOS failures I've seen on one hand and in all of those cases the issue occurred during a BIOS update. Even that's not a deal breaker anymore as a lot of times you can blind flash them.

Yes I can order the exact same chip but I would like to just keep one type in stock and use it for all card which need it. That's why I would like to know whether they are structurally similar enough to do that. :)
At the very least you would need the right pinout and specifications. That is, you would need the correct size ROM, etc.
 

Ready4Dis

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A lot of times they are pin compatible, but research would be necessary for sure. Also as mentioned, pretty uncommon for the bios chips to be bad unless they were failed flashes and don't have any flashback/dual bios features, but it's been pretty hard till kill rom chips for a while now. Since most GPUs would be roughly based on oem design, I imagine most would share similar (electrically) chips even if a different brand.
 

GiGaBiTe

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I'm not sure how you reached this conclusion. I've serviced PC's of every kind for over two decades. Literally 10's of thousands of systems and I've only seen a few GPU's, motherboards etc. with bad BIOS ROMs. I can probably count all types of BIOS failures I've seen on one hand and in all of those cases the issue occurred during a BIOS update. Even that's not a deal breaker anymore as a lot of times you can blind flash them.

I used to think SPI EEPROMs would last forever until I started getting a bunch of different devices in with bit flips from cosmic rays, or stuck bits that required multiple erase/write cycles to clear up. One chip I had to trash because it would never return correct contents after writing.

But to answer the OPs question about using a different SPI EEPROM, the answer is "maybe". There are common jelly bean SPI ROMs of a given spec, but they all may have slight variances that make them able to work or not with a specific device. As for using a larger ROM, it may be possible, but you'll have to pad the ROM image file with zeroes to fill up the entire EEPROM. Usually you need to pad the lower half of the ROM and put the data in the upper half of the ROM.
 
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I'm not sure how you reached this conclusion.
These cards only start a few out of many startups and when they do they don't have the same problem - sometimes they crash on the boot screen other times they get to the login or even run windows. And if you look up the bios version on a failed startup via another graphics card GPU - Z says "unknown". As far as my research goes that is a clear sign of a faulty bios chip 🤷‍♂️

But to answer the OPs question about using a different SPI EEPROM, the answer is "maybe". There are common jelly bean SPI ROMs of a given spec, but they all may have slight variances that make them able to work or not with a specific device. As for using a larger ROM, it may be possible, but you'll have to pad the ROM image file with zeroes to fill up the entire EEPROM. Usually you need to pad the lower half of the ROM and put the data in the upper half of the ROM.
Thanks, that should help me out.
In case I remember I'll give you an update on whether it worked.
 

primetime

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These cards only start a few out of many startups and when they do they don't have the same problem - sometimes they crash on the boot screen other times they get to the login or even run windows. And if you look up the bios version on a failed startup via another graphics card GPU - Z says "unknown". As far as my research goes that is a clear sign of a faulty bios chip 🤷‍♂️


Thanks, that should help me out.
In case I remember I'll give you an update on whether it worked.
I agree with Dan here....but best of luck
 

Dan_D

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I used to think SPI EEPROMs would last forever until I started getting a bunch of different devices in with bit flips from cosmic rays, or stuck bits that required multiple erase/write cycles to clear up. One chip I had to trash because it would never return correct contents after writing.
I never said they lasted forever or didn't fail. However, I am saying that failures of those chips are extremely rare. I've serviced, used and handled more computer hardware than anyone could ever count and I don't think I've ever seen a BIOS failure that didn't coincide with a bad BIOS flash. I'm not saying it can't or doesn't happen, but if it was a normal problem I'd have run into it at a few times at least.
These cards only start a few out of many startups and when they do they don't have the same problem - sometimes they crash on the boot screen other times they get to the login or even run windows. And if you look up the bios version on a failed startup via another graphics card GPU - Z says "unknown". As far as my research goes that is a clear sign of a faulty bios chip 🤷‍♂️
If these were all tested in the same system, I wouldn't be so sure it's an issue with the BIOS on the video cards. Again, it's more than a little unlikely you would have even one card out of a 100 with such a problem.
 

SvenBent

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These cards only start a few out of many startups and when they do they don't have the same problem - sometimes they crash on the boot screen other times they get to the login or even run windows. And if you look up the bios version on a failed startup via another graphics card GPU - Z says "unknown". As far as my research goes that is a clear sign of a faulty bios chip 🤷‍♂️


Thanks, that should help me out.
In case I remember I'll give you an update on whether it worked.

I have to agree with Dan too.
I have with a conservative count probable 10.000 PC built/repaired, and very rarely run into Bios defective issues and mostly its from bad flashing.

There is a difference between being a sign, and being a for sure conclusion.
 
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robijito123

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Have you tried just reflashing the bad cards with a good bios say from gpuz database? Especially with mining craze / personal experience you can flash the cards wrong/ unstable settings. But in all my years as stated above I have not really see a bios chip actually fail. On an old tyan server board I did have to hot swap a chip to flash to a good config before though.
 
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Is it even possible to use nvflash on a selected card? I've searched but found nothing regarding this topic. I don't have a dedicated spi programmer (jet) so my only option would be an arduino?
 

Dan_D

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Is it even possible to use nvflash on a selected card? I've searched but found nothing regarding this topic. I don't have a dedicated spi programmer (jet) so my only option would be an arduino?
In theory it won't let you flash an incompatible card. The format of the flash program and file has to be compatible with the actual ROM. That said, I've never tried that so I don't know if it would be a problem or not.
 
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I don't want to flash an incompatible card - sorry for the imprecise language there - I have to select the card I want to flash the bios onto since the affected cards can't show an image themselves or are unstable I have to use another Nvidia card to do the job.
 
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As far as could find out there are two major series for SPI flash chips - 24 and 25. Both have 4, 8, 16 and 32MB models which should be pretty much compatible as long as you have enough capacity and don't mess a 24 up with a 25 or vice versa.
But is there a convenient tool to fill up a binary file to the needed size? Couldn't find one.

I have also tried to flash some of the cards but I always get an ID missmatch. On one card I even tried everything single available BIOS for the specific DIE available on Tech-powerup - ID missmatch. And since I can't even install the backed up BIOS from this card Im quite certain that something on this card is done.
 
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