Page 2 of 3
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 14:38
by LagBuster
DWM performance at 62.9 Hz is consistent, but I get repeated frames during video playback. If I go back to 60 Hz DWM is stuttery but I don't get repeated frames...
EDIT: Although, now I'm thinking that maybe those repeated frames don't matter. At 62 Hz I get exactly 2 repeated frames every second (60 fps video with madVR), which makes sense. I suppose it only matters statistically speaking, then?
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 19:05
by RealNC
Well, 30FPS video needs 60Hz. Obviously. 24FPS video needs 48Hz or 72Hz (or 96Hz, or 120Hz, etc).
(This is why 120Hz is such a good desktop refresh rate and preferred even if your monitor can do 144Hz. 120Hz matches 24FPS, 30FPS and 60FPS video, which are the most used video frame rates.)
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 19:17
by LagBuster
RealNC wrote: ā09 Dec 2019, 19:05
Well, 30FPS video needs 60Hz. Obviously. 24FPS video needs 48Hz or 72Hz (or 96Hz, or 120Hz, etc).
(This is why 120Hz is such a good desktop refresh rate and preferred even if your monitor can do 144Hz. 120Hz matches 24FPS, 30FPS and 60FPS video, which are the most used video frame rates.)
Yeah, I guess so. I'm only using 60 Hz because of 4K. With madVR I can tell it to change to any refresh rate when the playback starts, but it's not ideal.
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 19:54
by Chief Blur Buster
LagBuster, do you have VRR turned on or off?
A compositor with VRR enabled, sometimes has occasionally erratic dips in refresh framepacing. Not always, but it does sometimes deviate from the max-Hz framerate.
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 20:00
by LagBuster
Chief Blur Buster wrote: ā09 Dec 2019, 19:54
LagBuster, do you have VRR turned on or off?
A compositor with VRR enabled, sometimes has occasionally erratic dips in refresh framepacing. Not always, but it does sometimes deviate from the max-Hz framerate.
It's off, Chief.
Right now I'm testing 60.003 CRU Hz, which gives me the closest frequency to real 60 Hz, and I haven't noticed any stutters while web browsing yet. But with the YouTube 4K 60 fps video it's the same story.
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 20:59
by LagBuster
I will try to do a proper frame time analysis tomorrow or in a couple of days, and then I'll have more information.
EDIT: I went ahead and did a couple quick ones just now. This is what I'm talking about:
Default 59.981 CRU Hz
OC 62.9 CRU Hz
Sorry for double posting, didn't realize that I can only delete my latest post.
Re: Why are refresh rates "off" by a bit?
Posted: 09 Dec 2019, 21:27
by Chief Blur Buster
That's quite weird that framepacing is better at 62.9 Hz than at 59.981 Hz.
There must be something abnormal going on. Are you sure this is a single-monitor setup? The only time I saw this happen was when using a multi-monitor setup, where the Hz is at least slightly different between monitors. Windows has a really bad time synchronizing when multiple things are going on simultaneously on different monitors. For that situation, I temporarly disable all secondaries and only prioritize the main monitor.
Also, verify for power management quirks. There might be some erratic enabling/disabling of power management if your video uses less than 5%-10% of GPU, it sometimes interferes with framepacing of video playback because when so little GPU power is used, it starts power-management, which then starts interfering with framepacing sometimes -- a recurring problem that plagues TestUFO sometimes. Try changing power plan to High Performance and seeing what happens.
Re: Why are refresh rates "off" by a bit?
Posted: 10 Dec 2019, 07:36
by LagBuster
Chief Blur Buster wrote: ā09 Dec 2019, 21:27
That's quite weird that framepacing is better at 62.9 Hz than at 59.981 Hz.
There must be something abnormal going on. Are you sure this is a single-monitor setup? The only time I saw this happen was when using a multi-monitor setup, where the Hz is at least slightly different between monitors. Windows has a really bad time synchronizing when multiple things are going on simultaneously on different monitors. For that situation, I temporarly disable all secondaries and only prioritize the main monitor.
Also, verify for power management quirks. There might be some erratic enabling/disabling of power management if your video uses less than 5%-10% of GPU, it sometimes interferes with framepacing of video playback because when so little GPU power is used, it starts power-management, which then starts interfering with framepacing sometimes -- a recurring problem that plagues TestUFO sometimes. Try changing power plan to High Performance and seeing what happens.
Chief, I only have one monitor and one DP cable plugged in, but I noticed something strange going on. It seems that sometimes Windows doesn't recognize my monitor properly, and that results in CRU saying there's no active profile, which is weird because I can change to the custom refresh rate that I set using CRU, so that custom profile must be active somehow. I took some screen captures so that you can see what I mean.
If I run CRU's restart64.exe this behavior gets fixed.
Regarding power saving modes, I'm seeing that Windows power plan only affects CPU clocks, not GPU clocks, but High Performance vs. Balanced made no difference. There doesn't seem to be any way of forcibly disabling GPU power saving states (not for my old GPU, anyway).
Re: Why are refresh rates "off" by a bit?
Posted: 10 Dec 2019, 10:10
by LagBuster
Re: Why are refresh rates "off" by a bit?
Posted: 10 Dec 2019, 11:08
by RealNC
Never seen anything like this. Only thing I can think of is that something you installed in your machine messes things up. Some driver, some utility, something...
