Crossfire Issue - Horizontal White Lines

[dalekphalm]

Hey everyone, so I recently installed a crossfire setup in my system, and I'm encountering issues in 2 games (All that I've installed so far) where there are white horizontal lines that flow up and down (Or perhaps just down very fast, like watching a tire spin) across the screen.

The 2 games are: Crysis (Original) and Deus Ex: Human Revolution.

The system is:

EVGA X58 SLI LE board (pn: 141-bl-e757-rx)
Xeon W3520 at stock
1x Gigabyte HD 7770 OC Edition
1x Sapphire HD 7770 GHz Edition
Windows 8 Pro x64 with all Windows Updates
Newest NON BETA AMD Drivers
Newest AMD Application Profiles

Link to Picture of Board

I have the Gigabyte card in Slot #1 (x16) and the Sapphire card in Slot #2 (x8). They are very close together (1/4" spare space if that). I'd have preferred to use Slot #3 instead, but it's only a x4 slot and I imagine that's too slow to use a video card with.

I've searched into this, and apparently it was an issue lots had when Crysis 1 and other similarly aged games were first released.

"Solutions" were suggested such as:
Forcing V-Sync on all games using CCC (Didn't work)
Enabling V-Sync in-game (Didn't work)
Enabling Windowed Mode (Did work with Crysis, but NOT a solution)

So far, I've been unable to find a permanent solution. Does anyone have any ideas? Disabling Crossfire makes the games work, but then I don't gain the benefit of the 2nd card.

 

[Abit667]

Try a different crossfire bridge and/or putting it on the other crossfire finger.

 

[Fooshnik]

Those cards only have one.

There's probably not much support for the 7770 in xfire since most people probably don't do it. The eVGA motherboards don't have a reputation for being the most stable. Will the xfire bridge reach from the second (x8) to the fourth (x8) slot? If not I'd try the x4 anyway as I don't think it would be a huge bottleneck for a 7770 (benchmark to check).