Hey I have problem.
I have 3x GTX ASUS DUAL 6GB
1x GTX GIGABYTE 3GB

When I connect 3x GTX ASUS DUAL 6GB PC detects only 2 cards, when I change the card for GIGABYTE it shows 3.

The problem is that it can't show 3 GTX ASUS DUAL 6GB Cards, when I swap cards all the time only 2 are working fine.