Viewer performance v18.5 b2

I have updated my Nvidia driver from 516.25 to 528.95.

Playback 4K in Viewer 1 and Viewer 2 is no longer smooth in v18.5b2 (The lower right indicator is still at 29.97). I don't use Subview. 2nd monitor (View on = Monitor view 4) is no problem.

(The settings for both monitors are 10bit)

Fusion Studio v18.1.3 and Nvidia 516.25 is OK.
Fusion Studio v18.1.3 and Nvidia 528.95 is OK.

Fusion Studio v18.5b2 and Nvidia 516.25 is OK.
Fusion Studio v18.5b2 and Nvidia 528.95 is NG.

Which driver version do you recommend?

Does the issue go away if you disable 10bit output from the Fusion settings?
If yes then you need to set the frame rate to your monitors refresh rate in the NVIDIA control settings.

@UserNoah 10bit output was unrelated.

I found the cause. It is "Use Float16 Textures". (Preferences>Tweaks>GPU Usage(change from OpenGL?))
Turning it off solved the problem. Turning it on will reduce all UI performance during RAM preview.

— Use Float16 Textures: If your graphics hardware supports 16-bit floating-point textures, activating
this option will force int16 and float32 images to be uploaded to the viewer as float16 instead, which
may improve playback performance.

My 4k footage is int16. So I added ChangeDepth node and converted it to float16. Performance is back!!

"Use Float16 Textures" of Fusion Studio v18.5b2 with Nvidia 528.95 is not working.

V18.5 Beta 3, Playback on viewer is still not smooth with "Use Float16 Textures" and Nvidia 528.95.

Fusion Studio v18.5b2 and Nvidia 516.25 is OK.
Fusion Studio v18.5b3 and Nvidia 518.03 is NG.
Fusion Studio v18.5b3 and Nvidia 528.95 is NG.