No real time playback possible (anymore)

Hello everyone,

I am having a strange experience with my Davinci Resolve software and hope anyone here can help me.

Short Version:
After upgrading to a dual GPU setup (mainly for testing purposes, GTX 970 + GTX 1060) Resolve was able to provide a smooth UHD 24fps realtime playback. This even worked when adding multiple grading nodes, masks etc. First strange thing here was, that when using Noise Reduction, Qualifier etc the framerate would drop to ~10fps and stayed there even when I would undo that operation. Even after closing, reopening Resolve and creating a whole new project the playback rate would stay at ~10fps and the GUI being laggy and providing a late response to inputs. Only a computer restart would resolve the issue.
After switching to only the GTX 1060 and properly uninstalling / reinstalling drivers 24fps playback and fast GUI would not be possible anymore, so I switched back to the dual GPU setup, where I am not not longer able to get the live playback.

Longer Version:
Having only the GTX 970 as a graphics card I could only get live playback until the graphics card ran out of memory (which happened really fast on a UHD timeline). So getting a GTX 1060 6GB version I hoped to test both, a dual GPU setup and a graphics card with similar performance and more RAM.
After first installing the 1060 GPU-Z showed a good drop in GPU-Memory usage and Davinci utilizing both GPUs (after setting "use display gpu for computing".
When using Noise Reduction or Qualifier, which let the framerate drop, a bottleneck could nowhere to be seen. None of CPU, GPU, GPU memory, RAM and Storage showed full utilization. The same applied when the live playback could not be reached in a new project.
I then uninstalled the GPUs using DDU and reinstalled Nvidia drivers after taking out the GTX 970. GPU usage then was at 87% max, GPU memory at 3/6 GB and playback at 13fps.
With the feeling that the 1060 would not be powerful enough to provide a live playback, I switched back to the dual setup, again with reinstalling drivers. After that when playing back CPU utilization sits at 30%, GPU utilization at 2% (1060) and 4% (970), RAM 8/32 GB, storage not nearly fully utilized.
After installing a fresh copy of Windows 10, Nvidia drivers and Resolve, the problems still stay. At this point I don't know what to do anymore.
Even when telling Resolve only to use one or no GPU - still no 24fps and no fast responsive GUI. Tried with lowres timelines or different playback codecs - max 14fps.

System setup:
Intel i7-5820k 6-core
32GB RAM
SSD Boot Drive
Dual-SSD Raid 0 as Footage Drive
SSD as Cache Drive
BM Decklink Mini Monitor 4K
GTX 970 4GB / 1060 6GB
Windows 10

I've tried the following in all of my configurations:
- Switching Cache Drive / Location
- Using newest and older Nvidia drivers (430.81 and 388.31)
- (De)activating GPU usage in Resolve
- Switching to different resolutions and playback codecs
- Using different source footage
- (De)activating Decklink Card


Using Resolve 14 on Windows 10 with all updates installed and high performance mode in power management.

Is there something that I'm missing or could try to further inspect the problem? Does anybody have an idea on what's not working here?
I initially was hoping to test my new BM Micro Panel but was forced to return it now, since I don't have a real scenario to test it.
Thanks for anwers!
Bela

Maybe an obvious one but easy to overlook. I did beat my skull for nothing one time on this.
Check performance mode is activated in resolve. Makes all the difference in the world if its off.
Also set resolve to use cuda and not auto.

Hello Glenn,
thanks for your reply. Unfortunately performance mode didn't make a difference in any of my scenarios. I also tried to manually set acceleration to CUDA without success.

[Peter Chamberlain]

Can you try 14.2.1 that was just released?