I am using 79.11 for GF420 Go, and they are good, but I play only Fallout and other old games ;)
I am not sure if it's happy story - my previous drivers were 79.11 - for me no big changes so far - I haven't noticed any performance increseases,...
I had the same problem yestarday - it was the second mission in British Campaign - Escape froum Toujane or something ;), anyway I switched to DX 7...