Monitor artifacting?

Got any clues on what could be causing this?

https://youtu.be/D53w92O-dpc

you can see very breifly white lines going across the screen, not at the same places in the screen either, early in the video the lines appear near the top, other times near the bottom. this is while playing a game but it happens on the desktop, in VLC media player...

and its not consistent, it will go hours without happening and then suddenly happen again.

it is not cooling, as it happens with 0 load on the GPU and 100% load. Only started happening fairly recently. Tried a different miniDP port on my 295x2, still happens. Could it be the cable? I hope its not the $600 4k monitor or the $1500 graphics card...

It could be a driver issue. Do you have the latest driver installed? When was the last time that the system was blown out?

Looks more like some intermittent interference band or something on the monitor itself, leads. Mains borne interference, or something.
Poor quality DisplayPort lead with bad shielding. Badly soldered plugs/sockets worked loose.
Another external box nearby maybe completely separate from your PC/Laptop.
The latter of course you can move away to test, use another different brand of DislayPort lead.
Possibly a monitor PSU fault.