Well first of all: Good luck with that

Hmm sounds like the actual BIOS update went bad, which usually shouldnt happen. Not sure whether flashing from win7 is a good idea but maybe you can kind of initialize a boot to flash from there. If all fails you - or someone who does this on a regular basis - can still burn a new rom (like this selfmade one here
http://www.eeweb.com/project/circuit_projects/pic-and-eeprom-programmer ) with a working BIOS.
And yeah, I stopped buying hardware online a couple of years back when I had a CD Burner that "should be working" according to the support, but it for the hell of it wouldnt with my PC. It took me almost half a year to get my money back, because they insisted that they checked it and everything was fine, while when I finally got it back from the lab it still wouldnt work. Ofc they though it was a problem on my end and maybe it even was, but if its not working with the hardware I have I cant just replace my whole PC just to make one part work.