Geez Moar, take a chill pill. I'm not even the one you're aiming your rants at and I feel the sting. Maybe you should take note that the BIOS update did in fact solve the bulk of the problems before you go insisting it's hardware specifically. Either can be suspect, but there's nothing wrong with starting a deductive reasoning troubleshooting via checking software first, and in fact is quite common. A lot of first time builders that think only in terms of hardware and assume no software problems as Jaz was often waste money replacing parts they don't need to.
Jaz, you need to take software updates more seriously. C++ is very necessary, as much so as DirectX. I was having some problems on one particular game and after going to the C++ site and downloading the latest versions of each and their service packs, the problems went away. Make sure your NET Framework is updated too. Don't forget MB chipset drivers too and don't use just the MB driver disc for audio. Go straight to Realtek's page for HD Audio drivers to get the latest ones.
Proper Video driver installs are very important too. Sometimes repeated overwritten installs are only corrected by tools such as Driver Sweeper. Also try beta drivers. That said, you DO need to keep an eye on temps and voltages too. Make sure your GPU and CPU are within normal temps and check your PSU voltages. Also check for bad sectors on your HDD. I wouldn't be surprised though if that GPU is struggling a bit with W8. It's an odd pairing of GPU and OS. Just because Nvidia claims it compatible doesn't mean all the bugs are ironed out.