(please CC me as I am not subscribed to the list) > A screenshot would be helpful. Does these artifacts appear every single time > or sporadically?
The artifact appear at the same place every single time and seem to follow (in videos) a single set of colors (dark brownish areas). You can look at a screenshot[1] of the root window image as taken by imagemagick and the photo[2] of the result on the screen. [1] https://sml.zincube.net/~niol/tmp/screenshot.jpg [2] https://sml.zincube.net/~niol/tmp/screenphoto.jpg > I'd suggest to check RAM first of all with `memtest86+` and let it run > overnight. Not sure if test will get into memory area used as video memory > though. The system is otherwise quite stable, and also brand new. I have two RAM banks, and I tried with both alone with no improvement. I'll test the memtest but chances both of the RAM sticks are not good seem unlikely. > There was a microcode bug discovered recently in Kabylake-Skylake CPUs. It > causes memory corruption if I remember it correctly. It could be fixed for > certain CPUs by updating firmware for your motherboard or installing > "intel-microcode" package. It could be the cause for your issue. I had updated the BIOS/UEFI for this fix, but installed intel-microcode to be sure and this did not change anything (microcode version is the same and artifacts still present). Thanks for your advice, Alex
