Get the most out of your CPU or GPU and stop dropping frames
Published in · 4 min read · Jul 2, 2020
There are plenty of ways to tweak your OBS settings to improve your stream, but few options are as important as choosing the right encoder.
To put it simply, the encoder you choose will decide which piece of hardware is going to render your video. If you choose NVENC or AMF, you’re telling OBS to use your graphics processing unit (GPU), or if you choose x264 you’re telling it to use your central processing unit (CPU).
Aside from having a noticeable impact on your video quality, encoder settings will also have a big impact on your system’s performance. The right one will reduce the load on your PC and give you the extra power you need to record or stream at the best possible quality.
Let’s take a look at your options:
Right now, Nvidia is doing a great job when it comes to delivering meaningful features for streamers. Even if you put aside all the amazing things you can do with their RTX GPUs, like virtual green screens and AI-powered noise canceling, their NVENC encoder (NVidia ENCoder) was designed for content creators.
On all current GPUs (full list here) there is a dedicated chip designed solely for video encoding, which means your GPU doesn’t have to take away resources from games you’re playing when rendering video.
OBS can detect it automatically, so if you have the option to use NVENC in OBS, there’s really no reason not to at least try it. You might not want to use it is if you’re using x264 (more details below), which can deliver better quality video rendering when tuned correctly, but for most streamers who seek to strike a balance between performance and quality, NVENC is amazing and absolutely the way to go.
On a side note, video editors like Adobe Premiere and DaVinci Resolve can also take advantage of NVENC and save you a lot of time when rendering a video project. If you plan on streaming and video editing, and you’re in the market for a new PC, you might want to look into getting an Nvidia GPU.
Advanced Media Framework (AMF) is the encoder AMD graphics card users are supposed to use, but there’s a bit of a catch. While Nvidia is actively working to attract more streamers to their hardware by officially supporting their own encoder (NVENC), AMD has kept AMF open-source and rely on their community to keep it running.
It’s better than nothing, and if you have an AMD GPU, you should try AMF to see how it works for you. That said, if you’re in the market for a new PC and want to stream, there’s no reason to not choose an Nvidia card over an AMD one right now.
This might change in the future, but numerous tests have shown NVENC simply produces better video quality than AMF. It’s actually to the point where if you have an AMD GPU and a good enough CPU (like an i9 or a Ryzen 9), you may want to skip AMF and go straight to x264.
Have you got CPU power to spare? Using a two PC stream setup? x264 might be for you! Like I mentioned before, the advantage of other encoders like NVENC is that they use a dedicated chip on the GPU to take the pressure off your CPU.
The less work your CPU has to do, the better your games will run and the less likely you are to drop frames while streaming. But there is a slight trade-off in quality, and the reality is that x264 looks better than both NVENC and AMF when given enough power to do its job.
When selecting a x264 you can then adjust the CPU Usage Preset from ultrafast all the way down to slow and placebo. Faster speeds mean the encoder processes the video faster and uses fewer CPU cycles, but is also lower quality. On the other hand, slower speeds mean more CPU power is spent on each frame, and therefore the quality increases. Placebo is the slowest, but also so incredibly close to veryslow that it’s not even worth using (hence the name placebo).
Very fast is the standard, and fine for 99% of streamers. It’s essentially the benchmark by which NVENC and AMF are measured. Other good options include faster, fast, and medium, which is much higher quality, with medium being a significant jump from the baseline of very fast.
So when is x264 useful? Well, as mentioned before, if you have a killer CPU (like an AMD Ryzen 9), but you also have an AMD graphics card and want to avoid using AMF encoding, you might want to consider using x264 set to faster or fast.
Also, if you’re using an older PC and don’t have access to the NVENC encoder, use x264, set the CPU Usage Preset to veryfast, and use that as your baseline to see how your CPU handles it. If it’s going ok, adjust from there or leave it on veryfast.
Just remember this: a smooth but pixelated stream is always better than a choppy one. A lot of viewers are on mobile these days, so most can deal with low-resolution video, but few can handle dropped forms and frozen images.
