Not 100% sure but I believe someone on here said it was HDMI 1.4 and yes it sounds like a fault with your GPU.
@theswede
If you are just going to be using the 1 monitor for gaming i.e. the LG 29" then your current 290 is enough imo, however, to run those 3 dell screens for gaming then you will need 2x290's. You will see far more benefit with 2x290's than 1x290 8GB
HDMI etc. should work fine.
It is down to the game developers to support 21.9/2560x1080 so FC 4 doesn't have proper 21.9 aspect ratio support.
Hopefully flawless widescreen will update soon to support it:
http://www.flawlesswidescreen.org/
For that particular model, I can't say for sure but for 290's in general, I will be very surprised if we don't see them drop to <£200 when the 390/380 come about....
Saying that, the 290's atm are extremely good value especially the XFX one, £190 currently and once you sell the games on, it will reduce to about £130/140
I think I read before that you can crossfire different brands, you will need to post in the GPU section to check though.