How to fix games that stutter due to a CPU bottleneck

according to a calculator my PC has a CPU bottleneck of over 38% and judging from the red color that's quite bad right well spoiler it was but if you know what you're doing you can tune your PC to run smoothly even with such a severe bottleneck and this could mean money saved it could mean less landfill so if this sounds interesting to you then you are in the right spot because in this video I'm going to explain to you like your five how to deal with a CPU bottlenecked computer my machine has been getting old and while an upgrade would definitely be beneficial the main problem was my GPU which was abandoned by AMD some time ago I knew that somehow I had to upgrade it and I found a very good deal for a used 5700 XT and I brought it home started up a game and I was met with lots of starter you might think that a CPU bottleneck system is simply going to render games at a lower frame rate and while that's true that's not actually your biggest fear your biggest problem see a lot of games are are actually playable even at 30 frames per second with for a smooth experience the frame rate has to stay consistent over time and this is exactly the problem in a CPU bottleneck system the frame rate it radically jumps from one value to another creating stutter it's much better to have a smooth 30 frames per second compared to having 60 and then 9 and then 120 and then 15 and so on you might be tempted to believe that rendering 3D Graphics is solely the job of the GPU but the truth is a little bit different while your GPU is indeed optimized to render 3D graphics on your screen as fast as possible it requires help from the rest of your components in the form of instructions on what to render these instructions are named draw calls and explaining draws in depth can be the subject of many videos but for now the minimum you need to know is that all 3D objects rendered on your screen no matter their final shape and size are made out of triangles your GPU is rendering tens of thousands of triangles every single Le frame in a final image many of these tiny triangles will end up sharing some characteristics like their look or their material so to help the GPU in rendering them faster your CPU groups them together into a single draw call which is then sent to the GPU for rendering thus the GPU is heavily dependent on the CPU to prepare and send these draw calls in time for it to render them at a constant and preferably High pace and of course your CPU is also dependent on other parts of your system like your RAM but this is probably the subject for another video for this one let's think in more abstract terms and focus on the GPU and the CPU in an ideal scenario these two components are matched in such a way that in the majority of games the CPU is preparing the necessary draw calls faster than the GPU actually needs them thus fully utilizing your GPU and also leaving some Headroom for the CPU to do other tasks that may be running in the background of the game like maybe playing back a video or running a voice chat app or updating another game whatever the case may be in this ideal scenario monitoring your Hardware should show 99% or very close to 99% GPU utilization and the CPU should hover somewhere around 70 there's no like ideal value for the CPU because games are very different some have very complicated physics others have very large crowds others are simpler but you want to have some Headroom for the CPU to be able to hand handle some extra heavy calculations every now and then this ideal case can also be thought of as a slight GPU bottleneck and while bottleneck sounds bad a slight GPU bottleneck is actually okay but there's an emphasis on slight because obviously the slower your GPU is the worse your gaming performance and your visuals will be so unless you're using your CPU for some very intensive tasks it doesn't make a lot of sense to pair a very strong CPU with a very weak GPU cuz you're just wasting money in that case but the worst scenario is the one that I'm in which is the opposite a CPU bottleneck despite the GPU being fast because instructions for it don't come at a fast and steady Pace frame rates will suffer quite a bit especially in contemporary games overall the GPU won't reach its full potential obviously but this is not the biggest issue the main problem is the frequent dips in a very simplified explanation they happen because CPU load varies from moment to moment modern game engines use a lot of advanced caching mechanisms to achieve the best possible performance and this means that certain chunks of draw calls will be based on resources that are already precalculated that were used in previous frames and that can be reused and this in turn unloads the CPU for certain chunks of frames and this allows the GPU to render these chunks of frames at a higher rate but when the scene changes significantly when there's a new explosion happening in game or a new new physics simulation that's very complex the CPU now has extra work to do thus the GPU has to wait on the CPU to finish his job and this brings the frame rate down and if you repeat the cycle every few seconds you get stutter which can ruin many of your games if we're talking about multiplayer games then your CPU has an even harder job because now it has to keep track and replicate a lot more players so if you're playing something like Battlefield or Counterstrike you're going to see your CPU usage stay a lot higher compared to when you're playing something single player like control or Doom you might think that the solution is to Simply turn Graphics down because usually when your PC is struggling with a game on Ultra turning Graphics down to medium or low usually solves the problem right but there's a catch while settings that have a high CPU cost indeed need to be turned down to low sometimes settings that have a high GPU cost need to be turned up sometimes even up to ultra and besides this you're going to get a lot better results if you're using a 2K or 4k monitor as opposed to a 1080p one this can seem counterintuitive I know but it works because when you're rendering at a higher resolution at a at a higher visual Fidelity you're uploading a lot more work to the GPU making it slower and thus giving the CPU a little bit more room to breathe therefore the first step to make a CPU bottleneck less noticeable is to force your games to render at a higher resolution if you have a 2K or a 4k monitor then that's very easy of course but if you only have a 1080p monitor then don't worry because a lot of games will provide you a very useful setting which is usually called resolution scale or screen percentage but more on this a little bit later first to take a lot of the guess work out of the process it's a very good idea to install something like the Reva tuner statistics server which is the overlay I've been using so far in all of the gameplay footage the easiest way is to get it installed through MSI afterburner so use the link in the description to get the latest version and use the step shown here to install it to your machine and since After Burner is an overclocking tool now is the best time to mention it if your CPU and motherboard combo supported it's a very good idea to overclock your CPU to make sure you're squeezing as much performance as possible out of it today this isn't a very hard thing to do and the risks are quite minimal but they are there so you do need to know what you're doing and you need to use common sense there are tons of great videos and articles on the internet on the subject of overclocking and I linked some good ones description below and with afterburner installed it's time to configure the overlay the most important properties I recommend monitoring in the OSD are the CPU and GPU usage plus the frame rate and very important the frame time which I also want as a graph to see how it varies over time and we're going to use this overlay to confirm that the settings were tweaking or making the CPU work less and the GPU work more thus minimizing stutter bumping up settings related to texture quality filtering lighting quality Shader quality anti-aliasing screen resolution should generally be okay but pay close attention when it comes to stuff like physics or rag dolls foliage hair stuff like crowd density Dynamic lights or dynamic Shadows terrain or vegetation density or particle quality as these will probably have a high CPU impact setting up your game according to this guideline should get you to a good starting point to proceed with the most important setting which is the resolution scale we've been talking about a little bit earlier this allows you to force the engine to render at a high resolution which is then down sampled to your actual screen resolution and it's a great way to force your GPU to work a lot harder at minimum cost for the CPU this way you're artificially balancing out your components and as a plus you'll also get nice and crisp visuals albeit at a lower frame rate but if your GPU is strong enough to keep the frame rate above 60 then you're golden start by by setting it to 150 or 1.5 and then check the GPU usage and if it's 99% try decreasing it a little bit just to see if you can gain a little bit more FPS but if it's lower than 99% try increasing it maybe up to 200 unfortunately some games lack such a setting but in this case you can use your driver to fake having a higher resolution screen and here's how you can do this in the AMD control panel and here's how you can do this in the Nvidia control panel and after such tweaks just set your in-game resolution to something higher than 1080p so 1440p or even higher if necessary if smoothness is still not perfect if the game includes a way to limit the frame rate limit it to 60 this might not be ideal for high refresh rate monitors but it works because it forces the game engine to stop trying to render as many frames as possible all the time th reducing the workload for your hardware and leading to a potentially more stable frame time of course you won't be as competive comptitive with just 60 frames per second but you're on a bottleneck system so compromises have to be made here are some before and after shots of some of my games and a lot of them are obviously multiplayer so reproducing the exact same scenario is a bit hard but empirically there's a big difference in how they feel after tweaking and the overlay confirms that the hardware is working in a much more balanced way when the games are set up correctly and besides that staring went down considerably my machine is a lot more stable overall I have a lot more CPU Headroom that I can use to maybe watch a video or hang out on a voice chat app while I'm playing so I'd say that setting up games correctly brought a huge Improvement to the overall experience despite the Apparently severe bottleneck so in this case at least for me trading a higher FPS for more stability was worth [Music] it so here's a short recap of the steps you need to take to minimize stutter you can pause the video right here if you need a better Glimpse I hope you learned something useful today and if you're still feeling curious and you want to watch another video here are some suggestions we have been together on an odyssey of curiosity and I hope we can go on another one soon but until then have a great day [Music]

Channel: Andrew Dandrew

Views: 26,902

Keywords:

Id: WMbZp6Slo4Q

Length: 11min 33sec (693 seconds)

Published: Sun Feb 25 2024