System Framerate Issues

[Hiebly]

I've got kind of a weird FPS issue happening right now. Actual FPS are ending up higher than it should be.

 

For example when I set framerate target to 30 FPS with Half-VSync, it results in between 30.6-31 FPS. When I set framerate target to 60 FPS with V-Sync I get 62 FPS. And when I use Nvidia Inspector to limit framerate at 120 it actually sets the framerate to 127.1 FPS.

 

It's really annoying because it's causing stuttering even with V-Sync - with 30 FPS V-Sync there is 1 stutter per second, and with 60 FPS V-Sync there are 2 stutters per second (presumably because of the 31 and 62 FPS instead of 30 and 60). The 127.1 FPS doesn't make any sense to me at all.

 

I have 2x 1080P 60Hz monitors, primary one I'm using to game on is hooked up via HDMI.

[Marziman]

22 minutes ago, Hiebly said:

I've got kind of a weird FPS issue happening right now. Actual FPS are ending up higher than it should be.

 

For example when I set framerate target to 30 FPS with Half-VSync, it results in between 30.6-31 FPS. When I set framerate target to 60 FPS with V-Sync I get 62 FPS. And when I use Nvidia Inspector to limit framerate at 120 it actually sets the framerate to 127.1 FPS.

 

It's really annoying because it's causing stuttering even with V-Sync - with 30 FPS V-Sync there is 1 stutter per second, and with 60 FPS V-Sync there are 2 stutters per second (presumably because of the 31 and 62 FPS instead of 30 and 60). The 127.1 FPS doesn't make any sense to me at all.

 

I have 2x 1080P 60Hz monitors, primary one I'm using to game on is hooked up via HDMI.

Maybe it's because you're using HDMI rather than display port or VGA? 

[NeoFrux]

I've heard of this happening as a result of how frame rate is calculated on LCD's and more specifically over HDMI. 59(.94)Hz is actually what you're getting, since it's a multiple of 29.97Hz, the NTSC refresh rate for colour video. Even though we're past the days of analogue broadcast, TV broadcast is still done at 29.97, and as a result, HDMI expects 60Hz to really be 59.94Hz.

 

TL;DR, try setting a frame rate target 1-2FPS lower than your actual target.

[Hiebly]

17 minutes ago, Marziman said:

Maybe it's because you're using HDMI rather than display port or VGA? 

Maybe... I'll try using a DP cable.

[Marziman]

Just now, Hiebly said:

Maybe... I'll try using a DP cable.

Yeah there have been some quirks with monitors and V Sync or G Sync support for that matter with HDMI.  These are merely reports though.

[Hiebly]

Just now, Marziman said:

Yeah there have been some quirks with monitors and V Sync or G Sync support for that matter with HDMI.  These are merely reports though.

ugh man why do DP cables have to be so expensive. $22 min just for a display port cable

 

Do you know whether the issues with HDMI are on the GPU side or the monitor side? Curious if an HDMI -> DVI or HDMI -> DP adapter would do the trick, or if it would be a waste since the GPU would still think it's outputting via HDMI

[NeoFrux]

4 minutes ago, Hiebly said:

ugh man why do DP cables have to be so expensive. $22 min just for a display port cable

 

Do you know whether the issues with HDMI are on the GPU side or the monitor side? Curious if an HDMI -> DVI or HDMI -> DP adapter would do the trick, or if it would be a waste since the GPU would still think it's outputting via HDMI

I don't think it's really specific to one class of device or another, just any individual device's implementation. You could try going HDMI->DVI and seeing if that makes a difference, since how the devices talk to each other will change depending on which is connected. HDMI carries a DVI video signal, but without audio (usually) and without the assumption that it's a TV. If your card came with a HDMI->DVI adapter, it couldn't hurt to give that a whirl with the monitor and see if it works. Otherwise, a free solution would be to try dialing back your frame rate target by 1 or 2 FPS and seeing if that makes a difference.

[Hiebly]

4 minutes ago, Runefox said:

Otherwise, a free solution would be to try dialing back your frame rate target by 1 or 2 FPS and seeing if that makes a difference.

The problem isn't that I want specifically 30/60/120 FPS. No matter what framerate cap I enter, the end result is always higher. For example when I locked to 120 FPS, I got 127 FPS. When I locked to 119, I got 126, and when I locked to 118 I got 125.

 

When I lock to 60 FPS I get 62, when I lock to 59 I get 61, and when I lock to 58 I get 60.

 

What's particularly weird is the gap isn't proportional for the 120ish limits. Around 60 FPS, the end framerate is ~2 FPS higher than the target. Around 120 FPS, the end framerate is ~7 FPS higher than the target. Very bizarre. Not necessarily an issue for me, since ordinarily I don't play with V-Sync, but I'm actually testing a game at specific framerates to find variances in its physics calculations... but I'd like to know why my end results vary so much from the target FPS. Also curious if it's possible this would cause any sort of other issues. For example I have some mild stuttering issues with a couple other games, and it's possible this could be related. Also possible I'm just incredibly nitpicky and the stuttering happens to everyone (as it's not particularly drastic).

 

Basically just curious what's causing this to happen... the effects of it itself aren't of huge concern to me

[NeoFrux]

Hmm. That's really weird. Are you on the latest driver from NVidia? From what I'm reading, NVidia Inspector hasn't been playing well with FPS caps lately, and people are recommending using RTSS. Maybe give that a go and see if it makes a difference?

[Hiebly]

10 minutes ago, Runefox said:

Hmm. That's really weird. Are you on the latest driver from NVidia? From what I'm reading, NVidia Inspector hasn't been playing well with FPS caps lately, and people are recommending using RTSS. Maybe give that a go and see if it makes a difference?

Sure I'll try using RTSS, I already have it installed.

 

And this problem has existed with every driver I've used in the time I've had my 980 Ti. I really wouldn't be surprised if it's related to the HDMI. Prior to getting my 2nd monitor (and switching to HDMI on my primary one) I can't recall having this issue, and I only used a single monitor connected via DVI. Now I have my primary monitor hooked up via HDMI (DVI cord can't reach it in its new position unfortunately) with the secondary using the DVI cord.