I would'nt have thought so if the firmware is from the device manufactures ie. an update to fix issues, however if the firmware update is from a third party and has the purpose of circumnavigating anti-piracy controls or overclocking locks then the answer would be yes. I stand ready to be corrected of course but this is what I believe. HTH Peace
If you end up with an unbootable motherboard, usually you can get a new chip for about $20.00 or return it under warranty.
With a DVD drive you can always retry to update the firmware.
A video card is more of a problem. You need 2 in the computer to flash the proper one.
I have not seen manufacturer's refuse to honor a warranty due to missing or messed up firmware yet.