Gadgetory

welcome back to hardware box today's view is the first part of investigation into game streaming a topic that a lot of you guys request us to cover in our CPU reviews but we tend to leave out because it's quite complex to explore all the nitty-gritty details of streaming along with you know everything else in those reviews but over a couple of videos in the next few weeks we're going to look into streaming and provide you with a definitive answer on what sort of setup is the best for game streaming and what quality settings make the most sense to use today's video is mostly focused on streaming quality settings we want to find out what encoding settings deliver the best balance between quality and performance and how each of the various popular encoding modes differs in terms of results so a bit of backstory on our test platform before we get into the results one of the key things you want to figure out first is where the software encoding on the CPU or hardware accelerated encoding on the GPU is the better approach this is really one of the key battles because if GPU encoding is the way to go what CPU you need for streaming becomes largely irrelevant whereas if CPU encoding is better naturally your choice of CPU becomes a major factor in the level of quality not just in terms of consistency of streaming but game performance on your end over the last few months in particular GPU encoding has become more interesting because Nvidia updated their hardware encoding engine in their new GPU architecture churring while a lot of the focus went into improving a GBC compatibility and performance which isn't really relevant for game streaming at the moment Turing's new engine is also supposed to bring 15% better h.264 quality compared to the older engine in pascal so that's something we'll look into and see how turing stacks up against x264 software encoding on the GPU side we'll be using the RT x 2084 turing encoding a tight next pascal 4 pascal encoding and we'll also see how AMD stacks up with vega 64 the second part of the investigation involves software encoding with x264 using a variety of presets we're going to leave a cpu comparison with software encoding to a separate video in this video we're more interested in how each preset impacts before and Kali all testing in this video was done with the core i7 8700 K overclocked to 4.9 gigahertz and 16 gigabytes of ddr4 3000 memory which is our current recommended platform for high-end gaming in the future video we'll see how the 9900 K fares along with AMD's rice and CPUs for capturing this footage we're using the latest version of OBS and it's set to record at 1080p 60fps with a constant bitrate of 6000 kilobits per second these are the maximum recommended quality settings for twitch if you were just recording gameplay for other purposes would recommend using a higher bitrate but for streaming to twitch you'll need to keep it to 6 megabits per second or lower unless you're a partner we're testing the two games here we have Assassin's Creed Odyssey which is a highly demanding game on both the CPU and GPU something that CPU encoding struggles with and what's our horizon 4 which is less CPU demanding but a fast-paced title that low bitrate encoding can have issues with both titles present a bit of a worst case scenario for game streaming but in different and unique ways we'll start with GPU encoding because this is something that has been known to be rather terrible for a long time now the key bit of interest is to see how truing has managed to improve things compared to past GPU encoding offerings which were pretty much unusable next to CPU encoding options for Nvidia cards we use the env ink option in OBS and set it to use the high quality preset at 6 megabits per second there are a few other preset options but high quality produces as the name suggests the highest quality output for ambe's Vegas 64 we tried a range of encoding options both in terms of preset and bitrate with that much luck as you'll see in the comparisons shortly putting truing and Pascal's envying implementations side-by-side there's honestly not that much of a difference at 6 megabits per second both suffer from serious macro blocking effects and in general there is I guess a complete lack of detail to the image in photon horizon for in particular blocking is very noticeable on the road and looks terrible truing this encoder is perhaps a little sharper in some situations and is less blocky but really both a garbage and if you want to stream games this isn't the sort of quality that will impress your viewers AMD's encoder is even worse in that when your GPU utilization is up near 100% the encoder completely craps and stacks and can't render more than about one frame per second which wasn't an issue with the Nvidia cards I was able to get the encoded working with a frame limiter enabled which brought GPU utilization down to around 60% in ports horizon 4 but even with the quality encoding preset the quality Vegas 64 produced was worse than with even invidious Pascal cards with AMD's encoder out of the question right from the beginning let's have a look now at how in videos env Inc compares to software X to 64 encoded on the CPU in the slow-moving assassin's creed Odyssey benchmark env ink even using the high quality preset is noticeably worse than x264 very fast preset particularly for fine detail even when both are limited to just 6 megabits per second very fast x264 isn't amazing by any stretch but the level of blocking and the lack of detail to Turing's envying implementation is well it's terrible in comparison in the faster-moving forza horizon for benchmark Turing's and being does outperform x264 very fast in some areas envy ink again probably has slightly worse blocking but very fast really struggles with moving fine detail with this level of motion env ink is approximately equal to x2 64th faster preset there is no doubt however the x264 is fast preset is significantly better than env ink in fast motion and completely smokes it when there is slow or little motion this was also perhaps a little surprising considering Nvidia claims there nuturing envying engine for h.264 encoding is around the mark of x264 fast encoding or even slightly better at 6000 kilobits per second for 1080p 60fps streaming but from what I observed especially in Assassin's Creed Odyssey software encoding was much better when looking purely at software x264 encoding presets there are noticeable differences between each of very fast faster fast and medium in the slower moving assassin's creed Odyssey and ignoring the clear performance issues with some presets for now very fast and faster don't deliver a great level of quality with a lot of smearing blocking in some areas and a lack of fine detail particularly for objects in motion these two presets really to be reserved just for those who want to stream casually because the presentation when capture 6 megabits isn't great the fast preset is the minimum I'd consider using for a quality game stream particularly if you value image quality for your viewers it provides a noticeable quality job over faster to the point where blurred fine detail now has definition medium is a noticeable improvement again but the gap between fast and medium is smaller than the gap between faster and fast and as we'll see in a moment good luck using the medium preset on the same system the game is running on I did also check out the slow preset but at this point we're into diminishing returns for a massive performance hit for faster motion in Forza horizon 4 again I'd completely dismissed the very fast preset immediately because it's worse than envy Inc for this type of content unfortunately the tight bitrate limit of 6000 kilobits per second prevents any preset from doing true justice to the source material but once again medium gets the closest and provides an improvement over fast the faster preset looks terrible so again I'd suggest fast as the absolute bare minimum for this type of content really I'd recommend a medium at a higher bitrate but hey twitch has set the limit to 6 megabits so it's basically the best we can do of course image quality is only one part of the equation the other is performance and when you're streaming your gameplay from the very same computer you're playing on it's important that both your gameplay experience and the performance of the stream are adequate we'll start here by looking at GPU encoding and see how that affects performance enabling either pascal or cheering's envy ink engine affects the framerate of the game by around 10 to 20 percent depending on the game in other words you see a 10 to 20% drop in framerate when comparing capturing footage using envying to not capturing the game at all the more GPU limit of the game is the more of an impact envy ink will have which is why thoughts of horizon 4 is impacted more heavily than the heavy CPU user in Assassin's Creed Odyssey the good news though is while you'll be running the game at a lower frame rate with envy ink the stream itself will have perfect performance with no dropped frames even if the game is using a hundred percent of the GPU AMD's encoding engine doesn't impact the game's framerate nearly as much but it drops about 90% of the frames when the GPU is being heavily used making it completely useless as we are discussed earlier software encoding performance depends on the type of game you're playing in the case of Assassin's Creed Odyssey which heavily utilizes both the CPU and GPU streaming using the CPU will have a noticeable effect on framerate and high quality encoding presets will struggle to keep up with the core i7 8700 K and the RT X 2080 playing Odyssey using our custom hardware and boxed quality preset we were only able to encode the game using the x264 very fast preset without suffering from frame drops in the stream output x264 very fast encoding also reduces the framerate of the game by 17% which was a larger reduction than simply using env ink very fast encoding is better visually than envying for this type of game so the performance head in I guess some sense is worth it however moving to even the faster preset introduces frame drops into the stream output with a frame drop rate of 8.5% the Apple is stuttering and hard to watch meanwhile game performance has dropped from 90 FPS on average to just 63 fps with the 1% low only just above 30 fps it's clear this preset is choking the system and it gets worse with the fast and medium process which seep frame drop rates of 62 and 82% respectively interestingly game performance is slightly better with these presets than with faster but I suspect that student being coda being overwhelmed which allows the game to get a small amount more CPU Headroom for rendering the game one strategy to improve performance might be to cut the game to 60fps as those watching your stream will be limited to 60 FPS anyway but with this cap in place the story isn't all that much better the fast preset still sees 9% of all frames dropped while the faster preset just scrapes in with no frame drops but with a 1% low in the game of around 40 FPS the only option to use fast would be to reduce the visual quality and try again but for this video we weren't really interested in optimizing assassin's creed specifically for streaming with our hardware with the 8700 k limited to very fast streaming or perhaps faster with a frame cap or even GPU streaming in this title it will be interesting to see how other cpus stack up in part 2 of this investigation but certainly with the 8700 K which is a high-end popular gaming CPU what we've shown here is typical scenario for streaming in a title that heavily utilizes the CPU and GPU those with lower tier CPUs and in particular lower core count Intel CPUs will run into this very fast limit more often and as we mentioned very fast isn't really up to scratch for high quality game streaming you want to get it down to that fast preset which at least in a heavily CPU and GPU demanding title isn't going to be possible in a lot of situations and introduces a lot of frame drops compared to thief even faster our x264 encoding preset as for Fort sunrise and for which is far less demanding on the CPU it's an interesting situation because software encoding on the CPU actually delivers higher game performance than hardware accelerated GPU encoding this is because there is plenty of CPU Headroom to encode on the CPU without eating into GPU performance using the x264 very fast preset impacted game performance by six percent looking at one percent lows but the difference between very fast and fast was only a further 5% drop despite the massive increase in CPU power required to encode using the fast preset on the stream side we saw no framedrops with the very fast and faster presets however moving too fast which was the minimum acceptable quality level at least in our opinion for game streaming that saw a 12% frame drop rate for the encoded stream so again when we're moving to that higher quality preset we're starting to introduce performance issues which is a bit of a disappointment considering the extra quality that the fast preset provides and of course with a 12% frame drop rate this does cause unpleasant stuttering in the stream however considering we are running the game at nearly 120 fps we can quite easily implement a 60 FPS cap to reduce the game stress on the CPU with that cap in place the fast preset becomes usable with zero frame drops in the output the cap also opens up the option of medium preset encoding although with the 8700 K we still saw around 2% of all frames dropped with the 60 FPS cap in place which isn't ideal if we wanted to go with medium encoding we'd have to look at reducing the games CPU load through quality saint's tweaks or perhaps getting a better quality CPU again will further explore what cpus may be suitable for medium encoding in this title in a future video but it does seem to be quite a lot more demanding on the cpu compared to the fast present even with frame caps in place so with all that testing done there's a few interesting takeaways here the key finding for GPU buyers at the moment is the chewings GPU encoding engine for h.264 isn't significantly improved compared to pascal and certainly doesn't turn GPU encoding into a viable option for streaming the only time I'd suggest using envy Inc is with fast paced high motion games with the system that cannot CPU encourage using the x264 faster preset or better games with less motion should be encoded using the very fast x264 preset rather than envy Inc and very fast should be achievable on most pcs that have been built with streaming in mind on the AMD front their encoding engine needs plenty of work to be even considered it doesn't work with high GPU loads and when it does work the output quality well it's terrible CPU encoding is obviously a more tricky story as what level of x264 encoding you can manage will depend on your CPU and crucially the type of game you're playing without 8700 k system we range from being stuck with very fast encoding in a cpu demanding game to being able to use the fast or even medium preset with the steady 60 FPS game output at decent quality settings in a less cpu demanding title but what streamers should be aiming for is to use the fast preset as a minimum that's the first preset with the Apple quality is decent enough at 6 megabits per twitch streaming and while it's not fantastic for fast motion scenes fast is much better than either the faster or very fast presets yet it's still achievable on decent Hardware depending on the game the medium quality preset is also worth trying for those with top-end systems but it's a bit of a diminishing return situation you require a lot more CPU power to encode using medium compared to fast and the quality improvement it is noticeable but it's not massive whereas moving from very fast or faster to fast it does use a lot more CPU resources to encode using fast but the quality improvement is also similarly quite large I wouldn't bother with the slow presets though those also have a diminishing returns situation in terms of quality for a lot more CPU utilization while it's nice to be able to game and stream on the one PC this advice it really only applies to casual or part-time streaming anyone who is streaming professionally or full-time should use a second dedicated stream capture PC with a decent capture card and CPU this then fully offloads the encoding work and it allows you to comfortably you say the media preset are even slower for the best quality streams without impacting your game performance it also means you won't need to think about modifying your stream quality settings depending on the game you're playing you simply be able to choose say the medium preset and just go with that for pretty much every game you're thinking of playing at this point though we've discovered what the optimal presets are from a quality perspective so in part 2 we can investigate which CPUs are capable of encoding at these presets so stay tuned for that as always you can subscribe to get our future content in your inbox consider supporting us on patreon to get access to our exclusive discord chat that's it for this video and I'll catch you in the next one