Monitor: AOC 24G2U/BK, matrix = Panda
Resolution: 1920*1080
Refresh rate: 144 Hz
Situation. AMD cards are really picky to get their VRAM idling. You must set vertical blanking to 77 (basically comply with CVT-RB/RB2 standard). Issue is FreeSync. If i change nothing else, then under some load that drops framerate to low values will suddenly cause monitor to lose image and "input not supported error" to come out on top.
After some experience i managed to tie issue down to both vertical blanking and FreeSync. After crap ton of resolution values bruteforcing i managed to get few things.
1) base CVT will work fine under test, but VRAM idle frequency will still be maxed out.
2) Frankly ANY horizontal blanking value above 246 (including) will work fine, but have VRAM idle freq. to me maxed.
3) If i will comply to both horizontal and vertical blanking values, i will always get crashes
4) Easiest test to check - AMD Oasis FreeSync Demo. Launch it, set FreeSync on, set framerate limit to Sweep, enter settings and constantly go resolution scale 10-300-10 step by step. Usually it breaks on first cycle.
5) Only way to fix this was to set minimum FreeSync refresh rate to 49+ from 48. Meaning only one refresh rate - 48 doesn't work propely. But then it will gladly comply to CVT-RB2 standard...
Who is at fault, why does this happen, is there any way out?
Small addition. My monitor goes into LFC mode starting from about 54 FPS by default, doubling them. And, i can use my monitor at 120 Hz as there should not be issues.
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