Nvidia has made BOLD claims, both at the launch of their new Turing (or RTX) graphics cards
and during CES 2019, about the improved Nvenc performance and quality - that is their GPU-based
video encoder that has become a huge hit among game streamers due to the benefits of streaming
and recording gameplay without taking a performance hit due to CPU encoding with X264.
Prior to this new 20 series of cards, the trade-off has always been that the graphics
card would record or stream with significantly less performance hit than the default x264
encoder, but at a lower quality.
I’ve received numerous requests to check this out and see if they live up to the hype
and Nvidia was confident enough in this improvement to actually send me out a RTX 2080 graphics
card to test for myself.
Yeah, me!
Crazy stuff.
Anywho - short answer is yes!
But let’s look closer.
The ModMic Wireless can boldly go where no mic has gone before…
This microphone can attach to any headphones, requires no additional wires, features very
Housekeeping out of the way - my testing was done with a beta of a new build of OBS Studio.
Nvidia has partnered with OBS’s creator to completely re-work how the GPU encoding
functionality works to save on resources.
Previously, frames had to be copied to system memory, then sent back to the GPU for encoding.
Now, the frames stay within the GPU, which keeps CPU usage even lower.
I’ve been using a beta build of this version for my testing.
My test system has an Intel Core i7-8700k at 4.7 GHz, 16GB of RAM at 3000MHz, and a
Founders Edition Nvidia RTX 2080.
Captures were done from a base Xbox One to an Epiphan AV.io HD capture card at 1080p
60fps, and a Playstation 4 Pro running at 4K downscaled to 1080p with a Magewell USB
4K HDMI Capture Plus card for good measure.
I'm not showing (much of) the Xbox captures here because I had some issues with them,
but most of the - they reflected what I had.
But in terms of - I had some framerate issues that were on my end.
I did some testing and comparisons between Nvenc and x264 at Veryfast, Fast, and Medium
CPU usage presets.
Nvenc was set to Max Quality, High Profile, with Psycho Visual Tuning on (something in
the new build), Lookahead off, and b-frames left on 2.
On the previous generation of cards, Pascal or 10-series, Nvenc was considered to be on
par with X264’s “VeryFast” CPU usage preset.
These “presets” are basically how intensely they use your processor to encode the footage.
This ranges from “Ultrafast” down to “veryslow” and “placebo.”
The “faster” the preset, the easier and quicker it is for your processor to encode,
but the lower quality the final encoding is.
Quality artifacts result in blurriness, grainingness, “macro-blocking” or squares in the image,
and so on.
There’s more factors that go into resource load, such as the decode mode of your capture
card or if you’re using Game Capture locally, etc. - but that’s the general idea.
Typically the lowest it’s worth going is “Medium” - which typically requires a
separate streaming PC to offload encoding onto.
“Medium” is the preset that people tend to want to achieve and thus is the standard
that I’m benchmarking against.
And by the way, all of my upscaling tests were done in Adobe After Effects, because
After Effects has a much more accurate scaler than Premiere Pro does, and Premiere has some
issues with how they scale footage, and all of this is running through YouTube compression
anyways, so I'll have some notes at the end about how you can check this out better for
yourself.
While previous generation cards may have only matched “VeryFast” x264 encoding, I’m
happy to report that in my testing, the new Nvenc on my 2080 traded blows in terms of
quality reproduction with the X264 Medium encoder.
This is super nitpicky testing at this point, but in many frames, Nvenc has a cleaner image,
more detail preserved, and in some odd takes, more saturation than X264.
It’s not perfect, and there’s a million use cases for encoding and your mileage may
vary, but thus far I’ve been quite impressed.
I’ve always felt like chasing the extra 1% of image quality on-stream was an absurd
and expensive rabbit hole to go down with multi-PC setups and buying processors more
powerful than you need - but having finally streamed a few times with Medium last year,
I do kinda get it to a degree.
If you’re worried about getting that level of stream quality, too, at this point Nvenc
is a perfectly reasonable solution at this point.
You get a nice quality and performance boost - Turing’s nvenc can do 8k 30fps now, too,
by the way, though it can’t work in OBS yet - and they contributed to a massive change
and rework of OBS’s graphics framework.
It’s a good time for streamers.
Thanks to the wonderful contributors to our Patreon, Donorbox, etc.
I will have the original recordings for the tests shown here so you can download them
for yourself as… running them through YouTube compression kind of destroys the representative
accuracy a bit.
If you want to buy a Nvidia graphics card for your own streaming rig, I’ll have affiliate
product links in the video description down below.
While you’re down there, hit the like button and subscribe for more tech education.
Who knows, maybe I’ll get to cover more Nvidia cards in the future, we’ll have to
see.