GPU impact on bigadv

[littlepuppy]

Guys, going to be adding 3, maybe 4 GTX460's to a 980x

What impact (if any) will this have on my bigadv frame time, currently circa 21 mins..

 

[littlepuppy]

Hmmmmm, my alternative is to have a 980x just doing bigadv and then a lower "cpu" and undervolted CPU just running the GPU's...