While on a fresh install of DayZ Experimental, UK first-person official server, I noticed that there is a significant drop in frames per second (FPS) when directly viewing the sun's rays and when looking in the direction of bases. The sun appears different in DayZ Experimental--there are significantly more rays and they are brighter. Video settings are consistent between standard DayZ and Experimental and generally low and medium. Average FPS drop is from 100-120 to 60-70 when the sun's rays fill the screen, and from 100-120 to 40-60 when near bases. In particular, there is a large number of wooden walls near Cernaya Polana that cause FPS drops to at times 40 FPS.

This doesn't seem related, but occasionally players in close proximity will all experience a less-than-one-second freeze where the game seems to stop or FPS drops to 0 or near 0.