Question / Help Dropped Frames when Recording in 4K, only 25% CPU usage.

[Ray2R]

Hello all, I am new to this forum. I have never had a problem with OBS up until the point where I got a 4k Monitor. So I wanted to try recording in 4k.

Okay so, when I record/stream in 1080p, I get no dropped frames at all and it uses an average of 9.2% of my CPU when I Record or Stream at 1080p60 2500bits/s.

When I do recording at 4k, I get like 15-20 FPS drops using vsync to max out my FPS @60, it drops to 42-47FPS when I press "Start Recording" in 4k. When I record in 4k, OBS only uses 25% of my CPU on average. I've read about that when high CPU usage there is a red text at the bottom left and that doesn't show up since I am only using 25% CPU and not 100% like the other threads I have read.

My settings are, Output (Tab) - Recording (Tab)
Type = Standard
Recording Format = MP4
Audio Track = 1
Encoder = x264
Rescale Output = yes, 3840x2160
Rate Control = CBR
Bitrate = 2500
Use custom buffer size = yes
Buffer Size = 0
Keyframe Interval = 0
CPU Usage Preset = ultrafast
x264 Options = crf=20
------------------------------------------------------------------------------------------------
CPU = i7-5930k
GPU = GTX 1070
RAM = 16 GB
I don't think any other specs. need to be listed.

 

[Ray2R]

Log is of 1080p60 Stream and 2160p60, when I stream and record at the same time my CPU usage is 76%.

 

[Ray2R]

Bump

 

[LightNightSC]

hey I have somewhat of a similar problem but i severely drop in frames with my obs to like 10 fps. I have tried MANY different methods like uninstalling - reinstalling, uninstalling my anti virus software cuz i heard in rare occasions it could be that, and even tried lowering my obs settings. So i definitely think it is either some setting in obs or software interfering with obs.

here is my log

 

[H4ndy]

Two-pass encoding seems to break it for you, disable it.

 

[xxAssassin349]

@Ray2R Your CPU is really overloaded. Try using NVENC instead of x264 because that will offload all the encoding load onto an encoder on your 1070, massively reducing CPU load. I believe Pascal GPUs can do 4K pretty well.

Output 'adv_stream': Number of skipped frames due to encoding lag: 67731 (109.3%)

@LightNightSC Your GPU is overloaded. You have to give OBS more GPU power. Reduce in-game settings or cap your frame rate.

Output 'adv_file_output': Number of lagged frames due to rendering lag/stalls: 77951 (69.0%)

 

[Ray2R]

@H4ndy @xxAssassin349
Okay, I have redone some stuff. Here is the Log. This is only Streaming in 1080p50. Not Streaming 1080p60 and recording 2160p60 at the same time as first log.

So I tested opening OBS and my frames dropped and when I recorded no additional frames dropped. It has to do with OBS itself. Right when I opened it up my frames dropped like I said in my first post bc I thought it was the streaming/recording but since my OBS was always on I thought it was the streaming that caused it.

However, what caused it was simply having OBS open. I checked in game, got good frames. Opened OBS, frames dropped. Closed OBS, frames back to good.

If my Monitor is 4k, so base canvas resolution is 2160p and the Output canvas resolution is 1080p does that down scaling affect performance?

 

[Conrad_5]

im having the same problem with my other monitors when i open up obs too. just dont understand what is making obs not work properly. i have uninstalled it many times and i dont know what is going on. its gotta be on obs end

 

[Kusunagi]

BUMP! Shadow play causes no performance loss like this but the minute OBS is open Boom everything goes super slow. Even if your not recording or streaming. This is on I7 4790K @4.6Ghz, 32GB Ram, GTX 1080 OC Amp edition, 500GB SSD

 

[Aernath]

I'm having the exact same problem, tested it with 1080p, zero frame drops, but when I'm in 4K as soon as I open OBS any game's fps drops half. So, if there's a solution I'd be glad. If not... Bump