I think the teeth of an 8x is different from 4x. But im not that sure. Anyway, 8x is insignificant in a "4x" generation card. An example of this is the original Geforce and i think even the tnt2. A 4x card w/c was built in "2x" times. But look at it through the years, these cards didnt performed well in games even where 4x is already standard. So I suggest, just leave your card as it is unless you REALLY need to re-flash your Videocard BIOS due to conflicts and bugs.