Help with OBS 4K recording, 1950X testing from someone?

Hardware Hub CPU
1

*If anyone has any other suggestions feel free, not sure GPU recording is up to the task exactly, it’s also bit rate and not CRF which is going to be better for local recording.

You can use VSR/DSR to run any monitor at 4k for testing.

Thanks to anyone who helps. For the Why I’m very interested in running older games at 4k and putting the footage up on youtube, already have a channel set up for it, just need the system for recording.

A Capture card wouldn’t solve the CPU horsepower part of the equation

Guess I’m just putting this call out there, I know a few people here have 1950Xs so I’d be interested in whether I should wait for Threadripper 2 or buy current gen TR…

Can someone run some 4k OBS tests for me? Recording whatever gameplay, Dota 2 is free and you can run a replay, mostly it’ll run at 4k on lower end hardware, or if you want to just jump in Half Life 2 and drive around that would be easy to run at 4k on any GPU. Game graphical settings don’t matter.

Currently I can do 4k recording, but it requires me to use the Ultra Fast Preset with CRF 18-20 I believe, and it uses 7 cores/14 threads, OBS scales great with cores. Here’s my current footage, it has some compression artifacting.

The games I’d be recording are mostly older games. However if the OBS work can only use 12c/24t then it means I can record modern games down the line.

So first thing I would ask is that in CPU Affinity set the game to use cores 0-7 so 4c/8t, then OBS use the rest of the cores/threads, 12c/24t. And have no background processes running.

For OBS settings, the following images:

CRF can range from 14-18 14 preferred, but if it needs to drop to 18 it’s not a big deal. 320 on Audio bit rate as well, because why not?

CPU Usage, Very Fast is pretty good and should be doable as it scales with cores, if it can do Faster without overloading that’d be great, and you probably want to record to an SSD to remove any potential bottleneck there. OBS will give you a warning if it’s overloaded, but maybe keep task manager open and watch the threads as well, hopefully it’s not riding at 100% usage, would maybe want some breathing room so it doesn’t end up dropping frames. Windows 10 is unpredictable after all.

CPU affinity

OBS Settings 1

OBS Settings 2

OBS Settings 3

2

With local recordings, I tend to go with CBR rather than CFR, but with how x264 works, CBR is practically impossible. The closest you can get is to set the bitrate and buffer size so that they’re identical.

Higher bitrates work better when you use superfast preset. In fact, veryfast is only necessary if you use VBR or CRF. For 4K at 60fps, I would go with 200mbps. You can ease processor burden by encoding “intra only,” which involves setting your keyint to 1. This needs a massively higher bitrate though. I recommend 600mbps for intra frame.

Also, especially at 4K, having a secondary OBS canvas GPU is extremely handy to offload the OBS canvas to a dedicated GPU while having your primary GPU render the game. Simply have one monitor per GPU, and set your primary display to your secondary GPU when you launch OBS, then switch the primary back to your more powerful GPU and OBS will stay on your secondary GPU.

3

Well dunno about 2 GPUs, but that’s what I’m at currently with just 1080p recording using a GPU

4

Don’t use NVENC or AMD’s accelerated video encode. Use x264.

1 Like
5

That’s the goal, but it just won’t do for 4k encoding, people keep suggesting the GPU accelerated stuff though

Like it takes 5 cores 10 threads to do 1080p CRF 18 Very Fast preset, guessing I just need more cores for 4k

6

You just need superfast preset, intra-only encoding, and a fast M.2 with a Threadripper build. That’s pretty much it.

7

That’s what I’m thinking I need, but I need to know how good it is exactly, how much headroom I got, need a way to test it for myself…

8

As long as you make the bitrate ridiculously high for 4K 60p, like 600-800mbps, superfast and intra-only produces really good results.

9

I’ll probably stick to CRF 14-18, seems to be fine from capturing 1080p test footage, just need more cores to scale it up to 4k.

Like I said in the post I can do 4K footage at Ultrafast CRF 18 with 7 cores/14 threads

10

CBR matters more sometimes for consistent quality rather than CRF which is still VBR. CBR also eases encoding and decoding stress.

11

Isn’t CRF lower file sizes in the end for comparable quality though? So far have looked into CoD WW2 and GTAV recording with it and it seems fine.Files

12

Yes, it lowers file sizes, at the cost of increased encoding and decoding stress. For instance, if you’re going through foliage, that is murder on something that has to encode in real time, so CRF has a buffer to try to encode complex scenes as fast as possible. If it can’t, it drops frames.

CBR, what broadcast digital TV uses, stays at a constant bit rate and overly complex details don’t bog down the encoder causing it to skip frames.

1 Like
13

Well thanks for the info, just need to decide on a 1950X or waiting for threadripper 2…

14


I hope that helps a little.
15

The game footage after 1 minute is horribly laggy. What did you do different compared to the first time?

16

Dedicated 8 threads to mining monero.

1 Like
17

Does that get you any profit?

Thanks, I assume that was Very Fast CRF 18 or better for the 4k CS:GO recording?

18

Untitled
Untitled.png3840x2160 453 KB

19

Wonder what the exact settings are, but it looks solid enough for sure just using “Indistinguishable”

20

The 1950x just cant keep up when you add 8 more threads maxed out. I have tried 7,6,5,4,3,2,and one more threads with no problem in stream quality.