How would you know if a CPU would bottleneck a GPU?

[Akumatie]

I used to use a bottleneck calculator, but it came to my attention that they are inaccurate and completely false. Well apparency according to some guy I was speaking to.
I used to own a 3070ti and a 5600X config and I found that the 5600X was a bottleneck as the 1% and 5% lows were terrible in CPU demanding games like GTA 5, I was getting microstuttering and hitching all the time.
Then when I got a 14700K all the stuttering and hitching was gone. The calculator I was using the main one said the 5600X and 3070ti had a 2% bottleneck.
When I was giving advice today they posted a 5060 and a 7500f build, so I put the build in the calculator for a general overview, it had a 6% cpu bottleneck at 1080p, so I advise them to go up to a 7600X, but some guy had a fit and told me that them calculators are completely wrong and false and they are terrible. How am I meant to know how much FPS the 7500f can pull in a game then compare that to the 5060 performance which is not even out yet, as you would want the CPU to pull higher FPS than the GPU can for a smooth stutter free experience. As you are just throwing a bunch of frames to the CPU if that CPU cannot handle that amount of frames it will just stutter as it would be overloaded. But no I was wrong was using a calculator and suggesting a better CPU for a smoother experience or was I correct I really do not know? But I got blocked lol so we could not discuss further on the topic.
But genuanly whhen I look for a bottleneck on an already built machine I go to Intel presentmon then look at the GPU and CPU busy timing then go from there but I cannot do that to hardware I do not own.

[Millios]

Use MSI afterburner to check CPU and GPU usage

If one is near 100% and the other is not then you found the bottleneck

 

Btw as everybody with more than 1 day of knowledge will tell you
bottleneck calculators are a PoS scam, they dont show you anything but a random number

5 minutes ago, Akumatie said:

When I was giving advice today they posted a 5060 and a 7500f build, so I put the build in the calculator for a general overview, it had a 6% cpu bottleneck at 1080p, so I advise them to go up to a 7600X, but some guy had a fit and told me that them calculators are completely wrong and false and they are terrible.

Dude was rude but was right they are wrong false and terrible
should they have acted like that? No

Should you have answered with a bottleneck calc? Also no

6 minutes ago, Akumatie said:

How am I meant to know how much FPS the 7500f can pull in a game then compare that to the 5060 performance which is not even out yet,

You arent and you cant

you tell em "hey the card isnt out so we cant tell" and thats about the end of it

7 minutes ago, Akumatie said:

But genuanly whhen I look for a bottleneck on an already built machine I go to Intel presentmon then look at the GPU and CPU busy timing then go from there but I cannot do that to hardware I do not own.

Just look at specific combos on YT

They show FPS and using MSI afterburner they also show how much the GPU and CPU is used thus if there is any "bottleneck"

 

Really it seems to like you werent prepared to give accurate info and happened upon a jackass so you both were in the wrong

you for the BS calc, the other person for the improper reaction

[Akumatie]

1 minute ago, Millios said:

Use MSI afterburner to check CPU and GPU usage

If one is near 100% and the other is not then you found the bottleneck

 

Btw as everybody with more than 1 day of knowledge will tell you
bottleneck calculators are a PoS scam, they dont show you anything but a random number

Dude was rude but was right they are wrong false and terrible
should they have acted like that? No

Should you have answered with a bottleneck calc? Also no

You arent and you cant

you tell em "hey the card isnt out so we cant tell" and thats about the end of it

Just look at specific combos on YT

They show FPS and using MSI afterburner they also show how much the GPU and CPU is used thus if there is any "bottleneck"

 

Really it seems to like you werent prepared to give accurate info and happened upon a jackass so you both were in the wrong

you for the BS calc, the other person for the improper reaction

Yeah, that's my go to for going forward, is to check YouTube videos but not everyone has pacific hardware configs, so I thought "just put all the parts in the calculator for a general view" and that's what I have done for years, then I haven't had any complaints till now. Thanks for the insight about the calculators and about them being nonsense. Always best to look at the situation and see how we all could do better next time.

[Millios]

1 minute ago, Akumatie said:

I thought "just put all the parts in the calculator for a general view" and that's what I have done for years, then I haven't had any complaints till now.

No complaints isnt a good thing btw

 

The ones worried about a bottleneck are those who only know it as a buzzword aka they dont know what it is so you didnt get complaints cause the ones got the advise most likely were the ones who dont know (excuse the not so family friendly expression) jack shit about it aka "newbies" or teens who just want a PC and within 1-2 vids and reddit threads saw/heard the buzzword and went (oversimplified using caveman) "thing bad and can happen to me? How make bad thing not exist?Why bad thing always there?"

 

5 minutes ago, Akumatie said:

Always best to look at the situation and see how we all could do better next time.

It's the internet sadly

Attitude wise you can only change how you react to others and not vice versa

Let rude ppl be and try to learn what you did wrong if you did anything wrong at all

(PS just to hammer it in dont use bottle neck calcs like ever, they are just misinformation)

[Poinkachu]

43 minutes ago, Akumatie said:

so I put the build in the calculator for a general overview, it had a 6% cpu bottleneck at 1080p, so I advise them to go up to a 7600X, but some guy had a fit and told me that them calculators are completely wrong and false and they are terrible. How am I meant to know how much FPS the 7500f can pull in a game then compare that to the 5060 performance which is not even out yet, as you would want the CPU to pull higher FPS than the GPU can for a smooth stutter free experience.

We don't own a crystal ball is what some people usually reply with when someone asks here about something that has yet to exist or to be tested.

There's "Theoritically based on spec" and there's "Real world actual perf"

[Tan3l6]

50 minutes ago, Akumatie said:

I used to use a bottleneck calculator, but it came to my attention that they are inaccurate and completely false. Well apparency according to some guy I was speaking to.

It's inaccurate in general...

 

But the other thing to find it is to use either gut feeling or look at a lot of benchmarks and extrapolate results from them.

[Eigenvektor]

37 minutes ago, Akumatie said:

I used to use a bottleneck calculator, but it came to my attention that they are inaccurate and completely false. Well apparency according to some guy I was speaking to.

Yep, guy is right.

 

The bottleneck you're typically worried about is a CPU bottleneck, or in other words a situation where the CPU is the limiting factor. You generally want the GPU to be the limiting factor. Some component always is, otherwise you would have unlimited performance, which is not a thing.

 

As was mentioned above, this is visible in tools like MSI Afterburner or Intel PresentMon. If your GPU utilization is ~100%, then the GPU is running as fast as it can and as such limits your overall performance. In other words, a GPU upgrade is needed to get more FPS. If GPU utilization is well below 100% then some other component—possibly the CPU (but could also be RAM)— is the limiting factor.

 

So, why are bottleneck calculators garbage? Because the limiting component can vary per game, in game settings and even on a scene by scene basis within the same game. When reduced to a single number (e.g. by calculating the average) it becomes utterly meaningless.

 

For example if you play a game like Baldur's Gate 3, running around outside of town with no NPCs the GPU is most likely the limiting factor. But if you go into town with a ton of NPCs, suddenly the CPU has much more work to do (running both the simulation and handing work to the GPU). You could now be in a situation where suddenly the CPU is the limiting factor.

[Akumatie]

6 minutes ago, Eigenvektor said:

Yep, guy is right.

 

The bottleneck you're typically worried about is a CPU bottleneck, or in other words a situation where the CPU is the limiting factor. You generally want the GPU to be the limiting factor. Some component always is, otherwise you would have unlimited performance, which is not a thing.

 

As was mentioned above, this is visible in tools like MSI Afterburner or Intel PresentMon. If your GPU utilization is ~100%, then the GPU is running as fast as it can and as such limits your overall performance. In other words, a GPU upgrade is needed to get more FPS. If GPU utilization is well below 100% then some other component—possibly the CPU (but could also be RAM)— is the limiting factor.

 

So, why are bottleneck calculators garbage? Because the limiting component can vary per game, in game settings and even on a scene by scene basis within the same game. When reduced to a single number (e.g. by calculating the average) it becomes utterly meaningless.

 

For example if you play a game like Baldur's Gate 3, running around outside of town with no NPCs the GPU is most likely the limiting factor. But if you go into town with a ton of NPCs, suddenly the CPU has much more work to do (running both the simulation and handing work to the GPU). You could now be in a situation where suddenly the CPU is the limiting factor.

Yeah, I am mostly sceptical and worrisome about how limiting the CPU is compared to the GPU. As why would you buy a 5080 that can get 90fps in Z game but the CPU can only get about 80fps in Z game. As you aren't getting your full potential of the GPU and you could get stuttering as your GPU is just throwing too many frames at the CPU.
I would rather have better CPU that can do better than my GPU mainly because of smoothness in games. 
I agree that it depends on game, and them calculators don't really talk about the situations, if we talk about Red Dead Redemption 2 that would be more CPU demanding than a more GPU demanding game. 

[GuiltySpark_]

Video may be of interest. Normal person GPU's at a normal resolution and you get a great visual of how various CPU's scale. Interesting to note that only a handful of games had drastic CPU issues if yours wasn't up to snuff. 

 

 

[Eigenvektor]

4 minutes ago, Akumatie said:

As you aren't getting your full potential of the GPU and you could get stuttering as your GPU is just throwing too many frames at the CPU.

The CPU is the one throwing work towards the GPU, not the other way around. The CPU has to run the game engine's simulation, then generate draw calls based on that and send them to the GPU. The GPU is responsible for rendering the scene based on these.

 

A small CPU bottleneck usually isn't that bad. You will lose some fps, because the GPU can't start working on the next frame until it receives those draw calls, but stuttering usually only happens when the CPU is way too slow.

 

Here's a video where JayzTwoCents limits the CPU in CP 2077 on purpose. You can see that stuttering really only happens when the CPU is really slowed down, until then it's just a few FPS less than normal.

 

If the CPU isn't able to keep up, you can usually increase graphical details or resolution to increase the GPU's workload. While that won't result in faster performance, you should go back to GPU limited which can sometimes help avoid stutters.

[Millios]

1 hour ago, Poinkachu said:

We don't own a crystal ball is what some people usually reply with when someone asks here about something that has yet to exist or to be tested.

We dont? Since when?

 

1 hour ago, Akumatie said:

Yeah, I am mostly sceptical and worrisome about how limiting the CPU is compared to the GPU. As why would you buy a 5080 that can get 90fps in Z game but the CPU can only get about 80fps in Z game. As you aren't getting your full potential of the GPU and you could get stuttering as your GPU is just throwing too many frames at the CPU.
I would rather have better CPU that can do better than my GPU mainly because of smoothness in games. 
I agree that it depends on game, and them calculators don't really talk about the situations, if we talk about Red Dead Redemption 2 that would be more CPU demanding than a more GPU demanding game. 

Thats a bad analogy. It leaves out so much of the nuance

There are so many factors that go into what makes a good CPU and GPU combo that you cant just say "CPU does X frams and GPU does Y frames"
Its a matter of game, other hardware,settings, resolution,monitor/output etc etc
There are too many factors to say its either the CPU or the GPU since there are also other bottlenecks

Case in point, if you have a 60HZ monitor no matter what you get you can only use 60 FPS. Doesnt matter if you get a 9800x3D and a 5090 you will only get 60 FPS

[Poinkachu]

4 minutes ago, Millios said:

We dont? Since when?

I never seen Gandalf use crystal ball too.
Saruman did, but he was punctured by nearby spike in the stomach, so....

[Millios]

2 minutes ago, Poinkachu said:

I never seen Gandalf use crystal ball too.
Saruman did, but he was punctured by nearby spike in the stomach, so....

In "The Return of the King," Gandalf takes the black ball,the Palantír, back from Saruman after they meet
He used a Palantír  which for all intesive purposes is a crystal ball since they are the seeing stones ancient artifacts used for communication and seeing across great distances

 

He doesnt use it much tho specifically cause Sauron can corrupt ppl through it so he made the right decision to use it enough to not be corrupted by a cameo in lego batman (actually happened)

[Akumatie]

21 minutes ago, Eigenvektor said:

The CPU is the one throwing work towards the GPU, not the other way around. The CPU has to run the game engine's simulation, then generate draw calls based on that and send them to the GPU. The GPU is responsible for rendering the scene based on these.

 

A small CPU bottleneck usually isn't that bad. You will lose some fps, because the GPU can't start working on the next frame until it receives those draw calls, but stuttering usually only happens when the CPU is way too slow.

 

Here's a video where JayzTwoCents limits the CPU in CP 2077 on purpose. You can see that stuttering really only happens when the CPU is really slowed down, until then it's just a few FPS less than normal.

 

If the CPU isn't able to keep up, you can usually increase graphical details or resolution to increase the GPU's workload. While that won't result in faster performance, you should go back to GPU limited which can sometimes help avoid stutters.

I actually thought the GPU was throwing the frames at the CPU, but as you say the CPU throwing the frames at the GPU does make more sense thinking about it, I heard differently from a video a while back but it was prolly just a YouTube short nonsense.

[Eigenvektor]

17 minutes ago, Millios said:

Case in point, if you have a 60HZ monitor no matter what you get you can only use 60 FPS. Doesnt matter if you get a 9800x3D and a 5090 you will only get 60 FPS

I know what you mean, but that's not really correct. The game engine is only limited to 60 fps if you use V-Sync. With unlocked frame rate the game can run as fast as it wants, but you won't see more than 60 fps (and might get tearing).

 

If you use V-Sync and the game is limited to 60 fps, you would most likely see low usage on the GPU (and CPU). Though in that case you're not CPU limited, you're effectively "frame limited".

[Millios]

Just now, Eigenvektor said:

 With unlocked frame rate the game can run as fast as it wants, but you won't see more than 60 fps

Thats basically what I wanted to say so thx for phrasing it better my friend

[GuiltySpark_]

Intel PresentMon (as mentioned above) makes visualizing whats going on very easy. Graphs GPU Busy over Frametime. Ideally the two lines will be matched or near matched but if GPU busy drops well below frametime, that's the GPU "waiting" on something. Often the CPU (which includes that whole subsystem including RAM).

[Poinkachu]

10 minutes ago, Millios said:

In "The Return of the King," Gandalf takes the black ball,the Palantír, back from Saruman after they meet
He used a Palantír  which for all intesive purposes is a crystal ball since they are the seeing stones ancient artifacts used for communication and seeing across great distances

Still can't see future!

That's MiddleEarth/Mordor phone/skype man.

 

15 minutes ago, Millios said:

He doesnt use it much tho specifically cause Sauron can corrupt ppl through it so he made the right decision to use it enough to not be corrupted by a cameo in lego batman (actually happened)

O yea, Sauron is like those crazy high danger DIY tiktok video.

[Millios]

5 minutes ago, Poinkachu said:

Still can't see future!

That's MiddleEarth/Mordor phone/skype man.

It is possible to see the future through them but under specific situations 

Its a lil Show taking liberties and the concept and lore being a clusterF with some retcons but here they explain it better than I can cause I havent seen the movies in years

 

10 minutes ago, Poinkachu said:

O yea, Sauron is like those crazy high danger DIY tiktok video.

I mean... the palantir work with the mind giving users access to sauran and vice versa since they all the... was it 7? palantirs could communicate with each other.
When evil eye ball gets a hold of ya its kinda hard to fight him off

[OddOod]

The classic bottleneck question gets the classic response: It depends. The only way to know is to fool around and find out

[xg32]

12 hours ago, Akumatie said:

.

calculators mostly split out bs numbers, if a cpu like the the 9800x3d wasnt faster in games, people wouldn't buy them, so any cpu under it can be a bottleneck, depending on the situations, then you just gotta know what games are cpu intensive.

 

I was playing 33 recently with undervolts, was getting 4k 60-80fps on medium dlss performance, gpu usage was showing 100%, then i slap on the wilds and to my surprise 33 jumps to 60-105fps, guess i should have looked at per core cpu usage.
 

as it is i think zen 3 is now the minimum/recommended requirement for 120fps in alot of games, and 8core for 60fps, and likely a bottleneck to 5070 and up.