Bottlenecking Questions

[potatoproduction]

Hi,

I have a couple questions about bottle necking (CPU and GPU Bottlenecking):

1. Why do bottlenecks happen for cpu's?

2.gpu's?

3. is there away to tell that a cpu/gpu will bottleneck and cpu/gpu wiht out buying ( by looking at the specs)?

4. Can you fix it in anyway that doesn't require replacing?

5.How to tell that you have one

6.In a gpu bottleneck would your frame rate be the same even if you turn up the settings? 

 

 

 

 

[Cela1]

3 minutes ago, potatoproduction said:

3. is there away to tell that a cpu/gpu will bottleneck and cpu/gpu without buying (by looking at the specs)?

5.How to tell that you have one

Ask in these forums, you will also learn what parts make a bottleneck over time 

4 minutes ago, potatoproduction said:

4. Can you fix it in anyway that doesn't require replacing?

Overclocking can help slightly (if possible).

[minibois]

1. a CPU is bottlenecked when it can perform better, but is held back by something else in the system

2. what I said above, but with 'GPU' instead of 'CPU'

3. Looking at benchmarks of both the CPU and GPU to determine if the CPU or GPU would perform better with a better whatever. 

4. Overclocking can increase the performance, but not by a LOT.

5. looking at benchmarks and if you see that those benchmarks show better performance than you get in the same scenario

6. in theory that is possible yeah. Lets say, your CPU only allows for 30fps (that is not really how it works, but this is just an example) and you GPU allows for 30fps on high and 60fps on low. Turning up the settings to high, would make it so the GPU can only do 30fps, while the CPU can too.

 

Bottlenecking is something you want to avoid, because that just means you could spend less money on one thing and more on the thing that bottlenecks the system and could get better performance for the same money. It's not something you can completely avoid too and having some room for more performance on for example your CPU will allow you to upgrade in the future to a better GPU though.

[Guest]

1. When it doesnt have enough power to keep up.

2. Same story just switched roles.

3. Yes, you do research into how the performance of different components play along. Or you can look at price points and stay somewhat even. (GPU should be the most expensive part of a gaming PC).

4. V-sync or other forms of limiting FPS (V-sync doesnt remove the bottleneck but removes the horrid latency spikes that a CPU bottleneck can cause) or just scaling up/down the graphical settings.

5. Low load on a component while gaming.

6. Depends on the game.

Edited September 22, 2016 by Guest

[Guest]

1&2: When one of the parts are considerably faster, it will do stuff quicker (obviously) and will have to wait for the slower one to eventually catch up.

3. I usually check http://thebottlenecker.com/

4. Overclocking.

5. CPU's/GPU's utilization is way lower than the other.

6. Depends.

 

I hope I answered your questions.

[JJBTEXAS]

7 minutes ago, potatoproduction said:

Hi,

I have a couple questions about bottle necking (CPU and GPU Bottlenecking):

1. Why do bottlenecks happen for cpu's?

The CPU sends instructions to the GPU.  If the GPU is too slow for the CPU, this causes the CPU to slow down to the slower parts speed which means you aren't getting the most you can out of it, which is referred to as bottlenecking.

2.gpu's?

Same but in reverse.

3. is there away to tell that a cpu/gpu will bottleneck and cpu/gpu wiht out buying ( by looking at the specs)?

Benchmarks are really the only way.

4. Can you fix it in anyway that doesn't require replacing?

Overclocking the slower part will help, but only so much.

5.How to tell that you have one

Benchmark and compare to other people's results.

6.In a gpu bottleneck would your frame rate be the same even if you turn up the settings? 

If you're CPU is bottlenecking, it will result in lower framerates as it can't spit out instructions fast enough.  If the GPU is bottlenecking, increasing the settings will only make it worse.

 

 

 

 

[incarnate]

1 Cpus don't really get bottlenecked for the most part. The only other part they depend on is ram, so as long as you aren't running out of ram you're good to go. Again though, you don't really see this too often. Cpus don't depend on other parts other than ram so they can't be bottlenecked by other parts.

 

2 Gpus get bottlenecked by cpus. If a cpu can't send instructions fast enough to the gpu, the gpu suits there doing nothing for a time.

 

3 Before buying, look up benchmarks, learn cpu and gpu performances relative to each other. Ask other enthusiasts.

 

4 if your cpu is bottlenecked by the memory there's nothing you can do other than adding more ram (again rare af). If your gpu is bottlenecked by the cpu, overclocking the cpu can lessen it.

 

5 for cpus, if you're running out of ram constantly then it's being "bottlenecked". For gpus while gaming if you have a cpu core at 100% usage (or cores if the game uses more than one for draw calls) and the gpu is sitting at less than 95%ish usage and vsync and other framerate limits are OFF then you have a bottleneck.

 

6 if your gpu is bottlenecked by the cpu, turning up the settings well increase the usage. The framerate won't start going down until you reach 99-100% usage on the gpu.

 

So many people have wrong concepts when it comes to bottlenecks.

[Glenwing]

1 hour ago, potatoproduction said:

Hi,

I have a couple questions about bottle necking (CPU and GPU Bottlenecking):

1. Why do bottlenecks happen for cpu's?

2.gpu's?

3. is there away to tell that a cpu/gpu will bottleneck and cpu/gpu wiht out buying ( by looking at the specs)?

4. Can you fix it in anyway that doesn't require replacing?

5.How to tell that you have one

6.In a gpu bottleneck would your frame rate be the same even if you turn up the settings? 

When you're playing a game, every frame has to be calculated and constructed by the computer. The CPU and GPU (among other components) are involved in this, and each component has its own specific jobs to do with regards to preparing the frame. They can't do each other's jobs. So if for example your CPU is extremely slow and can only process a few frames per second, then that's all you're going to get even if your GPU is powerful enough to process hundreds of frames each second. Having a powerful graphics card doesn't "make up" for having a slow CPU, because they both need to complete their own separate tasks for the frame to be ready. So upgrading to an even more powerful GPU won't improve your framerate in this case, a situation we call a "CPU bottleneck".

 

Bottlenecking isn't a yes or no question though as some people seem to think, it depends on each specific piece of software. Every game has a different balance of how much CPU power vs how much GPU power it needs, so a configuration that might have a severe CPU bottleneck in one game might be just fine in another game.