You know what? I made myself a new list of choices based on what you said and what I found out (this never ends :tired:)
1) Buy an AMD 6990
With this card I get 2 x DisplayPort-DVI-adapter | 1 x DisplayPort-HDMI adapter.
If I want to eliminate screentearing I have to buy one adapter more, which will result in a total price of 625 euro's.
2) Buy an AMD 7970
With this card I get 2 x DisplayPort - Apple mini-DisplayPort | 1 x HDMI - 19-pens HDMI type A ( met adapter ) | 1 x DVI-I (dubbele verbinding) - 29-pin combined DVI.
I am not sure if I get the right adapters with this card, could anybody tell me if the Apple mini-Displayport adapters are the same as the ones I get with the 6990?
If yes, then this would cost me 510 euro's in total.
However, I would still have screentearing until the MST hub comes out. This means another XXX euro's and an extra adapter. Does an MST hub also increase input lag?
3) Buy two GTX560 2GB cards
With these cards I'd have no tearing and I do not have to buy any adapters. However, SLI does not always work properly.
This will cost me around 400 euro's.
Please give some valid arguments and/or benchmarks so I can make my mind up.
Moose
EDIT: I will also make some argument and look up benchmarks myself, but I cannot speak from experience. That's why I am asking you :)
I'm going to say exactly the same thing again. Buy a 7970. Multi-GPU setups can be a headache (a 6990 is a multi-GPU card if you didn't know). If you've never noticed the tearing before and you've played a game with v-sync turned off then the tearing won't bother you (it was there but you didn't notice it).
No one knows the details about the upcoming MST hubs - they're not out yet. I'm pretty familiar with the DP 1.2 spec though and it would make no sense for the hub to buffer any of the incoming signal so you shouldn't get any more input lag as a result of the hub.