Visual tearing issues with Crossfire 5770 setup

[ricsimas]

Hey everyone,

I'm running a pair of Sapphire 5770s (the regular ones, not Vapor-X), at stock speed.

I get this weird visual artifact of tearing about 1/3 of the way down from the screen. It looks very similar to having V-Sync off, as it's as if the upper 1/3 of the screen is slightly out of sync with the bottom 2/3s.

However, V-Sync is set to always on in CCC and within games, when applicable. I do not notice this in-game when playing Just Cause 2, for example, but it's very obvious in its menus. Other games with the same issue are Pro Evolution Soccer 2010 (all the time) and The Misadventures of P.B. Winterbottom (side-scrollers make it painfully obvious).

I'm on Win7 64-bit Pro with Catalyst 10.6. I've formatted and reinstalled Windows, tried various versions of Catalyst to no avail.

The only thing that cures it is disabling Crossfire with all other settings equal.

Any idea what could be causing this?

Thanks!

 

[ricsimas]

bigjimmy, isn't the "too many FPSs" issue what V-Sync should take care of? It seems like V-Sync is not working properly when Crossfire is on. The PSU should be fine (it's a 700W Cooler Master Silent Pro).

I've reseated the cards a few times, and tried changing the bridges around as well as running with 2 bridges and it didn't matter.

TheBiznes, this happened with every version of Catalyst I've had.

 

[ricsimas]

I'll try Rivatuner tonight, Biz, and report back.

bigjimmy, you may be right, but I'm pretty sure a single 5770 would get more than 60fps in the least demanding games I mentioned.

 

[ricsimas]

jkulas, I'm impressed that I don't see anyone else mentioning this. The issue is glaringly obvious to me and is enough to make me think that I should have sold my first 5770 and gone with a single-card setup instead of adding the second one.