http://en.wikipedia.org/wiki/Trusted_Computing
You did just install Vista didn't you? Vista takes full advantage of the TPM. I don't know for sure if the computer you have actually has a TPM chip in it. The BIOS upgrade probably didn't take that in to consideration. They wrote the BIOS for systems with, and without TPM chips. I suspect yours doesn't have the chip, but the BIOS makes Vista think you do, causing the error. It shouldn't cause you any problems if this is the case, just annoy you every time you boot up.