I get no karma from this. Please upvote so people can see and also fix their shit.
Okay, I did this and haven't had the graphics artifacting since, no matter what my in-game graphics settings are. I'm running a single GTX 560 TI and Windows 7.
First thing is you want to make sure your GPU drivers are up to date. Go to [1] nVidia's drivers site and find your card and update that shit. No matter how recently you did it, just do it.
Second, go to your Start menu, then Control Panel, and then nVidia Control Panel. This is going to let you configure your card IF you have the latest drivers installed. I'm not even joking about the drivers thing, update that shit to whatever the site says you should have.
Once you have NVIDIA Control Panel open, on the left side of the window you should see "3D Settings." Go ahead and click the "+" sign to expand that down if it isn't already. After that category is expanded, click "Manage 3D settings."
Now, on the main part of the window, you should be looking at a box with two tabs. One of the tabs will be labeled "Global Settings." Click that one.
Scroll down until you see "Threaded optimization" and TURN THAT SHIT OFF. It should be set to "Auto" by default, but we're not even going to fuck around with that. Turn it off.
There. You're done, it's fixed. Exit NVIDIA Control Panel, if it asks if you want to save changes, you best save that shit.
Fire up DayZ and go ahead and look at some dead soldiers to your heart's desire (you sick fuck).
EDIT: Hey, ATI card users/wiz kids/geniuses, if ATI cards have a similar setting, go ahead and look into turning it off and see if it fixes the problem. If it does, spread the word about that shit.
EDIT2: Fuckin' S128K DELIVERS with a possible ATI fix. I don't have an ATI card so I can't test it, somebody get on that shit.