7870 Crossfire Utilization Drops

boboman342 · August 3, 2014

I am having a slight problem when I use crossfire with my 7870's. I am using one reference 7870 Ghz edition with another Powercolor AX7870. I have set the core clocks and memory speed to match. I am using MSI Afterburner to achieve this (running 14.2 drivers from amd) because the only options I could get to work in CCC was the dam "enable crossfire x" button. I am also running 14.2 drivers because the newer drivers let crossfire x be enabled, but the second gpu doesn't even turn on. I have the FX6350 @4.4Ghz @1.456xxxx on HyperEVO212 (push pull) and am aware that this MIGHT be causing the cards to not run at full speed. The exact problem I have is where both gpu's are running near 100% usage when loading/changing settings in game (bf4) but once in game (playing) BOTH gpu's somehow decide they dont want to run at near 100% and sometimes drop <20%. I have uploaded 2 screenshots of my problem. While "in the menus" and "loading screens" both gpu's and cpu are around 80-90% usage, but from the in game screenshot it's a totally different story. Regarding my cpu overclock, I have disabled all cool&quiet features, ULPS, etc. I have no idea how/why this is happening and would like some help!

With crossfire disabled, i still get around 90% cpu usage and almost always 100% gpu usage when playing. I get BETTER frame rates with one card....

I play at 1920 by 1080 ultra preset and get 45-60fps with one 7870 and 30-120fps with crossfire. One weird thing that does occur, if I spawn in the middle of an online 64 player game, go into the menus, wait for gpu's/cpu to go to 80-90% and quickly go back to the game, my fps stays at 70-90fps until the usage drops back down to around 50% gpu. Can I force the gpu's to run maxed out? Even if I have a cpu bottleneck? I don't mean run at 100% speed, they do that already, but make them "process" all they can to help overcome the cpu?

For some reason in the screenshots, gpu2 clock/mem speeds were not captures properly, but i can assure you, while in game they are the same at 1100/1400.

In games like borderlands 2 the cpu AND gpu's both hover around 70-80% even in multiplayer.

Edit: I ran both gpu's at 1000core/1200mem and in game they get about the same usage. I have a corsair cx600m with 46A on the 12v rail and 600watts(as per recommendation for 7870xfire)