Not necessarily the memory that the issue ming, I have been having issues recently on my pc where I have been getting strange artifacts on screen, not too distant from what your seeing. Mine is like ill be doing nothing and then get horizontal lines across my screen, almost like a tv loosing signal or something. I put that down to either a bad OS or my hard drives crapping out, since I only noticed it after I installed my HDD raids into my rig. I thought it was my gpu crapping out but then I switched to the 3770k GPU and it still did same thing.
Ive since reinstalled my OS and I installed it using RAID mode as apposed to before when it was set to AHCI and I had to change service settings to make it work. Touch wood ive not had any artifacts yet even though ive got the HDDS back in.