So yesterday, I just built myself a new system with a Radeon RX 580. I spent this morning benching it on 3DMark with no problems.
Then tonight, when I benched 3DMark again, I'd suddenly get horrible artifacting. Basically, the screen would be split into several distinct strips, and each strip would independently jitter and artifact. The artifacting was so bad, and the strips were so distinct, that you couldn't even tell each strip was part of the same image as another strip.
I exited 3DMark and re-ran it several times, and the same thing happened every time. I checked my GPU temps, and they weren't getting above 75C.
Then, I tried playing Starcraft 2. For the first several minutes it was fine, and then the exact same thing happened.
Meanwhile, I had a second monitor, and none of this was happening. I would be getting artifacting on the first display while the second display still looked fine.
For example, when SC2 blew up and I exited to the desktop, the primary display was still artifacting while showing the Windows desktop, but the secondary display was displaying the desktop just fine.
Then I realized the first display was using DisplayPort while the second display was using HDMI. Maybe that was the culprit? So I connected the first display to HDMI and disconnected the second display. (The second monitor only accepts HDMI, so I can't simply swap them.)
I ran 3DMark again, and this time, no problems. Then I played SC2 again - no problems.
So switching from DP to HDMI seems to have solved the problem. But it means I can't have a multi-monitor setup anymore, since the Radeon has only one HDMI.
Also, I want to know *why* DP isn't working. Is it a defective graphics card? Defective cable? I can live with a defective cable, since I can just buy a new one. But I don't want a defective graphics card!
I'm seeing stories online of people with DP problems being told to get better cables. One article even says that gas-operated chairs (like mine) can create EMI that can interfere with DP. (https://support.displaylink.com/knowled ... ing-or-los)
So I've just ordered another DP cable from a different company, plus an active DP-to-HDMI converter from a third company.
But before I go spend a million dollars on different cables, I want to see if anyone has any other suggestions for how I might diagnose this problem.
Thanks.