his limit is his drives, and hardware.
tell him to try
www.speedtest.net and see what speed he gets there.
is it the other lads on the server thats selling it or enny one else? ( send a pm to me )
and for the amd cards, if i dont remember wrong, it can be the drivers thats bugging the cards, but i cant say for shure.
try googling around and look at tests
🙂heres a quick google hit i got :
http://hexus.net/tech/reviews/graphics/37253-three-screen-geforce-gtx-680-vs-radeon-hd-7970/laters z z z