M17x R2 680M driver assistance needed

I just got my 680M card installed in my M17x R2 and it seems to be working perfectly in Windows 7, but I'm having a fair amount of difficulty getting the drivers to install on Windows 8. I'm pretty familiar with modding INF's but for some reason I haven't found a driver version that will install properly. Any ideas would be awesome.

M17x R2 680M driver assistance needed