Version 2.1.1 of ProRender is only usable at all if I don't touch the render quality selection, because it's right to the desktop, and like the past versions when it crashes, 9 out of 10 times it leaves it in a state where the whole computer freezes up for all but 2 seconds about every 10 seconds. So if I am lucky I can get to shut it down to restart before it locks up completely. If it just crashes without becoming barely usable, I still have to re-start the computer because if I try to reopen Blender again, Blender will just lock up and crash anyway as soon as it gets to the gray screen and starts loading the plugin. If I can't get to the start menu and restart it I am forced to just press the reset button and force it to restart. That makes it really frustrating to try and evaluate these versions, so after 4 or 5 times that happens I always have to just go thru re-installing an old version of ProRender without full spectrum. I don't get any errors to report whenever this happens, so I kind of have no where to go with this, The only Noticeable thing with the version 2.1 of RPR was that when switching to rendered mode (full), the "Starting" time takes WAY longer than before, even with an empty scene it would take 30-40 seconds. I really wish I could make this work better, I have an all AMD system, with their latest products and I can't seem to get a handle on why a simple scene with almost nothing in it would crash so easily. I will continue using old versions, and I guess using my 2nd GPU will have to wait.
So with latest RPR 2.1.1 selecting both GPUs uses both GPUs. Selecting only Primary GPU(w/display) uses primary only. Selecting secondary GPU only, actually uses Primary GPU only. So the only way to use my 2nd GPU with ProRender is to use it combined with my primary GPU, but that way gives the EXACT same render times as just my primary GPU alone.(yet they are both being utilized, I verified it) Although Cycles WILL use each GPU independently if I choose, the performance is similar to RPR results, being that with the RX580 + RX5700 XT combined is about the same render time as the 5700 on it's own. and the 580 on it's own is slightly slower. Is this likely that splitting between the two GPUs is not going to be beneficial because the 580 is much slower, and is slowing the whole process down?