Timeline monitor settings - How it actually works?!

Explanation of timeline monitor settings (one on timeline’s ‘monitor’ tab, not the timeline itself) I was given is that they matter only if one uses external monitor connected to one of Black Magic’s playback cards and that they don’t come into the play at all if one uses PC type setup in which there is a single end consumer video card used by operating system for everything.

HOWEVER, as I was trying to figure out how to make my playback smooth(er) and eliminate (or at least minimize) dropped frames I am experiencing I started, on suggestion, changing resolution of monitor and observed following:

When I decreased resolution playback seemed to become smoother, less frames were dropped, and overall CPU consumption seemed to drop.

When I increased resolution playback seemed to become choppier, more frames were dropped, and overall CPU consumption seemed to increase.

This is in direct contradiction with everything I came across about behavior of timeline’s monitor because if it didn’t come into play on systems like mine (Windows PC with single consumer video card connected to single consumer monitor) then I shouldn’t have observed any changes in behavior when I changed its resolution.

So does anybody have DEFINITIVE answer on how EXACTLY resolution of timeline’s “monitor” works and comes into play, please?

Resolve speed is almost always dependent on system power (CPU, RAM, GPU), I/O speed (drive speed and connection), and choice of source material codec. Drivers and OS can of course have an effect as well, as can timeline settings, timeline length, resolution, speed, render cache, and so on. External RAIDs with fast connections will yield better performance most of the time. Slowdowns can also occur due to highly-compressed codecs (like H.264/H.265), high frame rates, Fusion compositions, Magic Masks, OFX plug-ins, noise-reduction, or Optical Flow speed-changes that stress systems resources.

It is true that monitoring at a lower resolution might stress your system resources less.

Jason Bowdach has more to say about Resolve performance in this article:

https://blog.frame.io/2020/02/24/davinc ... rformance/

It is true that monitoring at a lower resolution might stress your system resources less.

Jason Bowdach has more to say about Resolve performance in this article: ...

Thank you for reply and link to Jason's article! If monitoring at lower resolution plays a role in workload on resources even on system that uses single video card doesn't that mean what almost everyone else is saying (that this matters only if one is using BMD card for second external monitor) is incorrect?

Thank you for reply and link to Jason's article! If monitoring at lower resolution plays a role in workload on resources even on system that uses single video card doesn't that mean what almost everyone else is saying (that this matters only if one is using BMD card for second external monitor) is incorrect?

Even if you're not using an external monitor, you're still monitoring using the Timeline resolution in Project Settings. That's what affects everything else.

Trust me, most people can edit pretty well at (say) 720P on an iPad, but it might grind to a halt if the timeline resolution is set to 4K. Huge difference in performance.

The same limitations apply whether or not you use an external display for color.

Thank you for reply and link to Jason's article! If monitoring at lower resolution plays a role in workload on resources even on system that uses single video card doesn't that mean what almost everyone else is saying (that this matters only if one is using BMD card for second external monitor) is incorrect?

Even if you're not using an external monitor, you're still monitoring using the Timeline resolution in Project Settings. That's what affects everything else.

Yes, when I am not using external monitor then I am monitoring using resolution for timeline I am on so one would think leaving timeline's resolution unchanged and just changing value under 'monitoring' tab for that timeline wouldn't / shouldn't result in playback's performance change yet my experiment indicates that it does.

Yes, when I am not using external monitor then I am monitoring using resolution for timeline I am on so one would think leaving timeline's resolution unchanged and just changing value under 'monitoring' tab for that timeline wouldn't / shouldn't result in playback's performance change yet my experiment indicates that it does.

No, because the processing also occurs at a higher resolution because of the timeline setting. This is all covered in the manual and in Jason's piece I linked to above. Rendering also takes more time (and more processing power) with a 4K timeline than with, say, an HD or 720P timeline.

Yes, when I am not using external monitor then I am monitoring using resolution for timeline I am on so one would think leaving timeline's resolution unchanged and just changing value under 'monitoring' tab for that timeline wouldn't / shouldn't result in playback's performance change yet my experiment indicates that it does.

No, because the processing also occurs at a higher resolution because of the timeline setting. This is all covered in the manual and in Jason's piece I linked to above. Rendering also takes more time (and more processing power) with a 4K timeline than with, say, an HD or 720P timeline.

I understand how resolution of timeline impacts resources. I am having trouble understanding how 'monitor' resolution comes into play. I will have to re-read Jason's article and manual.

That blog post has nothing to say on this matter. It's not the answer you want, but the display in the playback window is for reference only, so if you get better playback at a lower resolution, it makes sense to use it, because you're not losing anything by doing so if there's no external monitor, via clean feed or decklink.