Screen sometimes turns off and won't turn back on (Vega 64 on 10.14.6)

[nicksoph]

I'd ask in a thread that deals with whatever green, my limited understanding is that it isn't loading if you get purple lines and there is often something to do in config.plist

 

[macs_forever]

My system is mostly stable except for this. It has only happened a few times, but I'd like to narrow it down. The most recent time I was just browsing in Chrome and the screen suddenly went to sleep mode.

Single monitor connected to Vega 64 over DP, running at 4K@60.

Sleeping and waking works normally.

When this happens, I can still connect over ssh, smb etc. but I cannot connect over Screen Sharing.

Any ideas?

My EFI is attached.

I had this problem with an MSI RX580. I replaced it with a Vega 64 and it fixed it. Check for overheating. make sure your card is getting plenty of fresh air. That same RX580 works fine in a cMP 2009. Whatevergreen would be my next guess.

 

[macs_forever]

I am connected using a DP 1.4 cable. Any idea how to test this? If I could trigger it, I could troubleshoot it...

Yes, use a different cable and see if the problem goes away!

 

[littlecreature]

This is all just troubleshooting since everything is fine with DisplayPort except for very occasional drops to black screen which I was hoping to diagnose.

The HDMI cable I am using is a known good HDMI 2.0 cable that I use on another mackintosh with an RX480. I have also tested running 3D games at 4K@60 under windows and it works.

Just for sanity, I tested another HDMI cable that doesn't do HDMI2 and it exhibits the same behaviour.

Case panel happens to be open at the moment and there is a fan on the base the pulls air up specifically for the GPU and it runs 3D games at 4K without a hiccup, so I think it is ok.