Recently got an e6430 with bios a A13. I wanted to downgrade to A12. Every time I do it, the process does the same thing. It has a progress bar saying it's preparing to update, but then just reboots and nothing changes. I've used DOS bootable USB, and Windows methods, neither is updating the bios.
I tried going to A03. Tried to going A18, A20, etc. But nothing ever works. The progress bar says it's preparing, then reboots.
Is there some setting I'm missing? I don't see some sort of "allow downgrade bios" option in the bios settings list.
There is a real possibility of bricking the motherboard CMOS by downgrading a BIOS. Updating the BIOS should be fine, but do them in order, A13-A14-A15 etc. and run them from within windows.
Thing is, I couldn't upgrade or downgrade the BIOS.
I got a replacement e6430 from the vendor that had A14, and I was able to downgrade to 03, then back up to the A12 that I needed correctly now.
Looks like it was a hardware issue that I couldn't update the bios at all.