Graphics Card Running Slower

[Lukasador]

Ok so basically i have 3 ti's. An MSI 780ti, OC ACX ti and a Classified. In the past the msi and oc acx ran fine in sli. For some reason after connecting any of the other 2 with the classified the 'other card' runs slower, that is, the memory runs at 810Mhz rather than 3500Mhz as would be expected hence bottlenecking the system severely. Ive tried different pci express lanes with different card configurations and the problem doesnt seem to go away. All drivers are up to date and the system says the cards are running in sli. It should be noted that in furmark both cards run fine and as expected though in Unigine Heaven one runs slower (as you can see in the picture). AC Black Flag also showed signs of decreased performance after comparing the fps of the sli setup (with one card running at 810Mhz and the other 3500MHz memory clock) compared to a single classified.

[AlwaysFSX]

Run each card by itself and see what afterburner says.

[niofalpha]

Is the Classified a 780 Ti or a Vanilla 780?

[Lukasador]

Why did you get 3 different tis? and what are you doing with 3 of them?

one of them is my brothers