SLI 1080 Ti CPU Bound

[sealthard]

Hi guys,

I'm building a new PC with a 7820x and two Strix 1080 Ti's and I heard that games can be bottlenecked or "bound" by the CPU if you run at 1080p, but will not have this problem at higher resolutions.

Sorry if I'm being dumb, but can anyone explain this to me? Surely the bottleneck will stay the same, so how can performance be any better?

Any advice would be appreciated. Thanks

Seal

 

[jacobweaver800]

Hi guys,

I'm building a new PC with a 7820x and two Strix 1080 Ti's and I heard that games can be bottlenecked or "bound" by the CPU if you run at 1080p, but will not have this problem at higher resolutions.

Sorry if I'm being dumb, but can anyone explain this to me? Surely the bottleneck will stay the same, so how can performance be any better?

Any advice would be appreciated. Thanks

Seal

well its simple, if you crank the Res to 1440p or 4k it puts more stress on the GPU's than the CPU because at a higher resolution it takes more graphics power to run games, therefore if your CPU bottlenecked at 1080p you might not be at 4k.

 

[Dulith1118]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

 

[jacobweaver800]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

Try 4k or drop a 1080 ti and play at 1080p

 

[sealthard]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

This is what I don't really understand though, how can the bottleneck even be reduced? Is it actually reduced or are the effects just somehow less noticeable?

The GPU will always be running certain tasks and the same for the CPU. It's not like adding more GPU power takes away from the CPU, because they're performing different functions, surely?

 

[Dulith1118]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

This is what I don't really understand though, how can the bottleneck even be reduced? Is it actually reduced or are the effects just somehow less noticeable?

The GPU will always be running certain tasks and the same for the CPU. It's not like adding more GPU power takes away from the CPU, because they're performing different functions, surely?

Lets say like this. When your gaming on 1080p only a limited amount of gpu and cpu is used specially when the gpu is high end like the 1080ti. When u bump the resolution to 1440p the cpu will be used a bit more say bout 5%- 10% more while the gpu usage will increase 20% or more. When you go into 4k cpu will use 10% more while the gpu will be using all its power to show those pixels. Like i said u cant remove it but u can reduce it. Understand now ?

 

[sealthard]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

This is what I don't really understand though, how can the bottleneck even be reduced? Is it actually reduced or are the effects just somehow less noticeable?

The GPU will always be running certain tasks and the same for the CPU. It's not like adding more GPU power takes away from the CPU, because they're performing different functions, surely?

Lets say like this. When your gaming on 1080p only a limited amount of gpu and cpu is used specially when the gpu is high end like the 1080ti. When u bump the resolution to 1440p the cpu will be used a bit more say bout 5%- 10% more while the gpu usage will increase 20% or more. When you go into 4k cpu will use 10% more while the gpu will be using all its power to show those pixels. Like i said u cant remove it but u can reduce it. Understand now ?

I kind of see what you're saying

 

[Dulith1118]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

This is what I don't really understand though, how can the bottleneck even be reduced? Is it actually reduced or are the effects just somehow less noticeable?

The GPU will always be running certain tasks and the same for the CPU. It's not like adding more GPU power takes away from the CPU, because they're performing different functions, surely?

Lets say like this. When your gaming on 1080p only a limited amount of gpu and cpu is used specially when the gpu is high end like the 1080ti. When u bump the resolution to 1440p the cpu will be used a bit more say bout 5%- 10% more while the gpu usage will increase 20% or more. When you go into 4k cpu will use 10% more while the gpu will be using all its power to show those pixels. Like i said u cant remove it but u can reduce it. Understand now ?

I kind of see what you're saying

Awesome. If ur planning to build it get a good 4k display and enjoy the games man.

 

[jacobweaver800]

Everything aboved mentioned but the bottleneck wont go away but it will be reduced alot while gaming on 4k. If your buying this to play on 1080p its a huge overkill. Try a 4k monitor perhaps.

This is what I don't really understand though, how can the bottleneck even be reduced? Is it actually reduced or are the effects just somehow less noticeable?

The GPU will always be running certain tasks and the same for the CPU. It's not like adding more GPU power takes away from the CPU, because they're performing different functions, surely?

Essentially the GPU tells the CPU it has frames already loaded to push to the monitor, but the CPU has to tell the GPU when to push certain frames, if the GPU's are too fast for the CPU, then the CPU can't tell the GPU's which frames to push fast enough, and this introduces a bottleneck. Only way to fix it is to get a better CPU or reduce your GPU horsepower by using slower cards or removing one.

 

[Dragos Manea]

Ok first of all the bottleneck is not removed, lets start like this, all cpus have a limited number of fps that can show, the cpu does not care about resolution or anything like that for the cpu 4k or 1080p is the same he know that lets say it can show 200 fps. The details (ultra or low) and the resolution matter for the gpu, at 1080p has to show 1million pixels at 4k has to show 4 mil pixels, that means the gpu has to work 4 times harder. Now here come the thing, if the cpu can show 200 fps at 1080p (how we talked earlier) but the gpu can show 400 fps at 1080p, the gpu will work 50% and the cpu will work 100%, this is cpu bottleneck, increasing the resolution to 4k, you got a much nicer view, much more details and the gpu will have to work 4 times harder that means from the 400fps at 1080p now at 4k will have 100 fps (400 divided by 4) but the cpu can show 200 fps (as i said for the cpu it does not matter resolution or anything else) now the gpu will work 100% because it has a lot more pixels to show but the cpu will work at 50%, this is known as gpu bottleneck (which is the normal way to be). A bottleneck must exist or else you will have an infinity of fps and the best way is that the gpu to work 100%. Only thing that can affact cpu is the number of solid particles because the cpu has to calculate the interaction between them, but nothing else affects the cpu.

 

[theonerm2]

Ok first of all the bottleneck is not removed, lets start like this, all cpus have a limited number of fps that can show, the cpu does not care about resolution or anything like that for the cpu 4k or 1080p is the same he know that lets say it can show 200 fps. The details (ultra or low) and the resolution matter for the gpu, at 1080p has to show 1million pixels at 4k has to show 4 mil pixels, that means the gpu has to work 4 times harder. Now here come the thing, if the cpu can show 200 fps at 1080p (how we talked earlier) but the gpu can show 400 fps at 1080p, the gpu will work 50% and the cpu will work 100%, this is cpu bottleneck, increasing the resolution to 4k, you got a much nicer view, much more details and the gpu will have to work 4 times harder that means from the 400fps at 1080p now at 4k will have 100 fps (400 divided by 4) but the cpu can show 200 fps (as i said for the cpu it does not matter resolution or anything else) now the gpu will work 100% because it has a lot more pixels to show but the cpu will work at 50%, this is known as gpu bottleneck (which is the normal way to be). A bottleneck must exist or else you will have an infinity of fps and the best way is that the gpu to work 100%. Only thing that can affact cpu is the number of solid particles because the cpu has to calculate the interaction between them, but nothing else affects the cpu.

It's not just the CPU. Most games have their own fps limit. Some games are coded in such a way that 144 fps is impossible. Other times the CPU is the bottleneck but usually the reason it's the bottleneck is because the game might not be entirely optimized for your CPU. Poor optimization is often the cause of what we think of as bottlenecking. It's true that a CPU will have an FPS limit but that limit will vary by game and it is dependent on how well the game is coded and optimized. Also a CPU can't do an unlimited amount of work. A CPU has limited resources. Each time a frame is rendered the CPU has work to do. The more fps the more work the CPU has to do. So as you can see it can only work with a limited number of frames per second. But that's not all the CPU handles. It also has to handle other programs you may have open, viruses if you have any, physics in the game unless that is offloaded to the GPU, Ai, and more stuff that I haven't listed here. The CPU has a lot on its plate. Open world games are usually some of the hardest to get high fps on because besides the work the CPU has to do for the frames it also has to handle a lot more ai and stuff like that. If you just want to see high frame rates at 1080p just try firestrike or some other mainly GPU focused benchmark.

Also 4K is approximately 8 million pixels. 1080p is around 2 million.

 

[Dragos Manea]

Also 4K is approximately 8 million pixels. 1080p is around 2 million.

It was just an exemplification so the OP could understand what is hapenning, yes cpu handles a lot more then what we said but it was justa simplification to understand what a cpu bottleneck is.

 

[jacobweaver800]

Also 4K is approximately 8 million pixels. 1080p is around 2 million.

It was just an exemplification so the OP could understand what is hapenning, yes cpu handles a lot more then what we said but it was justa simplification to understand what a cpu bottleneck is.

The short and sweet is, if you want to fix it completely you need a better CPU or you need to remove some GPU power by either removing a card or running SLI on slower cards like the 1070.