UPDATE: Fixed!? Here's what worked for me: All inside Radeon Software: Settings, Display, Override (right bottom): HDCP Support (disabled), HDMI Link Assurance (disabled). Combined with basically underclocking: Performance, Tuning, GPU -10%, VRAM -10%, Power +10%. Ran SOTTR for hours now with no problems, impossible before. Awesome. Game settings do not seem to matter (running fine at highest, not the cause).
I'm now trying to figure out exactly which of these settings helped the most. I hope it was HDCP related, not clocks or power. Will be undoing underclock, then power, then HDCP. (Enhanced Sync and other reported problematic settings are enabled, haven't noticed any problems, not the cause.) I've not changed anything else, nor the cable yet (not the cause).
Special thanks to mcgee (over here too), for some very useful hints!
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Any progress on this issue? I'm now experiencing this intermittent "black screen" problem. Screen goes black for 2-3 seconds, and this can happen every 10 seconds (but sometimes much less, almost randomly). Has only ever occurred during gaming (never in web browser, videos, apps, anything else). Less demanding games seem uneffected as well.
Didn't have or notice this issue until very recently (June, July, 2020). First noticed in Talos Principle (fairly demanding, DX11): more random, every 2-20 min. Much bigger problem in Shadow of the Tomb Raider (very demanding, modern, DX12): can take a few minutes to occur, then every 10-20 sec!
Biggest thing that changed recently is Windows 10 update (build 2004). Perhaps graphics and chipset driver update. I've been using this graphics card for a few years, in two builds now. It's been awesome, perfectly stable in old build (2016-2019, dozens of very demanding games). Upgraded PC last summer (2019-07, see specs, all new except GPU). Perfectly stable in this new build (XCOM CS, AOE DE, AOE2 DE, ME Shadow of War, more)... until this month. Maybe related: Upgraded monitor this spring (2020-04, UHD 4K, but games played windowed at QHD 2K or FHD), again no problems until now.
I purchased new cables as well (DisplayPort 1.4, HDMI 2.0, Monoprice) but they're not here yet. Have tried the DP and HDMI that came with monitor, neither helped (HDMI seems worse).
I had Radeon Settings adjusted when it occurred (10 Bit, Enhanced Sync, Adaptive AA, etc), but I've also tried full driver cleaning and default settings, to no avail. I've always adjusted fan settings via Radeon Settings, don't think it's a heat issue. (Fan stop off, 40-90% fan steps, 40-70 temp steps, logs report 60-65 C max.) For first time, I'm now testing other tuning (GPU and VRAM down 10%, power up 10%). Will update if any progress. I'm guessing this is an AMD driver (graphics or chipset) problem, and/or combined with Windows update changes, that will be ironed out in next few weeks or months. But I'm trying everything I can think of in the meantime.
Specs: AMD Radeon Software 20.4.2. AMD Chipset 2.04.28. Windows 10 2004. XFX Radeon RX 470 (RS XXX). ASUS B450-F motherboard (BIOS 2512). AMD Ryzen 5 2600 (stock). Corsair SF450M PSU. Philips 276E8VJSB monitor (UHD 27").
