We were updating BIOS for servers, and ran into problems with a few of them. The flash chip
on several of the servers were faulty; they were okay if left alone, and used for read only when server is starting up,
but attempt to flash new firmware on the chip, and the data gets corrupted. Essentially, several of the servers
were bricked, since the BIOS was corrupted.
To fix the bricked servers, we had to find replacement BIOS chip, reflash, and install into the bricked servers.
The faulty part was SST49LF040-33-4C-NH, 128x4K (512K). I looked around but the closest I could find was
SST49LF080A 33-4C-NHE which turned out to be 256x4K (1MB). i.e. double in size. Bought 20 pcs of those.
To flash the chip, I had to do what is known as hot flashing. Which is to get a similar server
with working BIOS, power up the server, remove the BIOS chip with the server running, put in a new chip, and flash.
The BIOS flashing software refused to write to the 1MB chip as the firmware is 512KB. Fortunately, a 3rd party software known as
uniflash was able to "pretend" the chip is SST49LF040-33-4C-NH, and write to it. The verify went ok, and after installing
the new chips into the bricked servers, the servers booted up fine.