I had the same issue with my dual AMD HD 7850's. I was having massive graphical corruption in the DayZ client and getting unusual crashes. I tried running FurMark to check for any sort of artifacts but it seemed to run fine.
I found out that both my graphics cards were on their way out. I was having memory issues with both cards that FurMark did nothing to detect. The only way I knew I was having an issue with the cards was by running a Litecoin miner. It was reporting a significantly lower hash rate than normal since it is heavily memory dependent. This wasn't a lot of information to go off of but I confirmed my suspicions later when I started producing a lot of hardware errors in the Scrypt based mining program. Although FurMark ran and looked fine, it apparently did not stress my GPU's to the point where the issue came up. This also never showed up in any game I tested (BioShock Infinite and Boarderlands 2).
I bought a brand new R9 280X to replace the 7850's and the issue never came up again.
I'm not suggesting you replace your video cards immediately. Try uninstalling your drivers completely and the reinstalling them. Also monitor your temps to make sure your GPU isn't experiencing some sort of temperature issue.
However be aware that programs like FurMark and Kombustor might not always show these kinds of hardware issues.