[HELP] Can i use 8MB Flash to store 4MB bios?

Hi,
My problem is my BIOS IC went bad and it is not storing some of bios contents.
My machine came with two Flash IC and the main one went bad. I’ve also tried to flash the bios dump which i had from the same IC, which i had flashed earlier and this time the IC is not accepting the data.
I have looked at the schematics and both the can be populated with 4, 8 or 16 MB flash IC.
I have also seen one other laptop which only had one IC and is running fine (same motherboard)
Now this is the only motherboard I’ve seen with a configuration like this:
4 MB BIOS Flash (Main Bios) and contains only BIOS Region.
8 MB BIOS Flash (Secondary?) which contains EC, GBE, BIOS and File Descriptor Region.
My question is can I replace my 4MB bios with 8MB, because its the only one i can find on Amazon.
and if i use 8MB flash, will i have to use 4MB dump or 8 MB dump.
I know my 4MB IC is bad and 8MB is good as it can be written properly.

I have working bios dumps of my machine and i know the faults, so can anyone help me out?

Hello buddy,

I am afraid that it will not work that way because in BIOS there is some sort of VSCC table of the chip that are supported so You need to get the same chip or similar.

Motherboards like DELL having two chips 8MB and 4BM and to work on that BIOS DUMP you need to combine these files to get the whole BIOS image.

VSCC_Snap.jpg

Screenshot_20210606-170241_Office Viewer.png


Thanks for the reply.
I will have a look at file descriptor, but i have already checked the contents of the bios region and they are 100% identical.
I want to gather some knowledge before doind something to the board.
After a lot of research i found a laptop similar to mine, which has less features than mine, but has same motherboard and looks also.
Basically that is the trimmed down version of my laptop.
And that only has one place populated with 8MB ic and the other is unpopulated which should contain 4MB ic.
It also has same bios as mine.
I cannot find a reliable source for a 4MB ic (25Q32BVSIG)
But i can find 8MB ic (25Q64CVSIG)
Can i put a 8MB ic in place of 4MB ic (look at the schematics)
And populate the content of 4MB ic in it, leaving other 4MB empty.
I will modify that but do you think it will work?

Similar ?? It is not AMD board ??

I really doubt that it will work … only way how to find out is you need to try it …

Thanks man, means a lot.

Capture.PNG


Here’s file descriptor
and it is Intel Board, Its an older laptop
so I guess I will just order and test.
Thanks again.

But I would say that it will not work … only with those chips in VSCC table there is 100 perc. guarantee.

Ok, but i was thinking of replacing W25Q32 (5th IC from VSCC Table with W25Q64 (4th IC from VSCC Table)
My actual bios size is 12 MB where the first half of data is on 8MB and other half is on 4MB

so if the system reads the data first from 8MB Flash and then from 4MB and the location is mapped, it will read 12MB from whole 16MB

[EDIT]
I desoldered and flashed both ic and my laptop turns on properly, except going to windows, linux is booting normally.

Many thanks for the help