GPU 's and Diminishing Returns

[D_Harris]

Can someone give me the specific reasons concerning how a GPU that is "too powerful" can adversely affect your system as far as game play, when compared to a less powerful GPU?

What exactly would a GPU do that would put it just out of the "sweet spot" and make a previous version a better option?

Thanks.

D_Harris

 

[Brian Boru]

Only thing I can think of is related to resource hogging & its results.

Physically too large:
♣ not fit in your case—check all dimensions!
♦ occupy 3 slots on your motherboard, narrowing your other upgrade or expansion options.
♥ degrade airflow within case.

Draw lots of power:
♣ overload your PSU.
♦ gradually overheat inside of case, causing 'discomfort' to other parts, mainly CPU.
♥ add noticeable amount to electricity bill.
♠ probably be noisy.

Be unbalanced for your system, if other parts 'can't keep up'—eg CPU can't play game at resolution or settings GPU can support, so GPU's capabilities are wasted.

 

[Kaamos_Llama]

Aside from what @BrianBoru has rightly stated, the reason people might tell you not to buy a top line GPU with a older or lesser CPU is that you would not see the difference in performance between a lower end card and a top line card. It wont have an adverse effect as such, so long as your other hardware is suitable, but you will have wasted money.

Basically you want your GPU at 100% as much as possible or youre not getting your moneys worth, if its running at 60% because your CPU is old and slow then you probably should have spent the extra on a new CPU/MOBO than bought a super fast GPU that isn't being used. Theres much more to it, but that's the essence of it.

This seems like a decent guide that explains it well if you wanted to know more.

 

[D_Harris]

OK. The reason for the question, which was difficult to word correctly, is I've read so many posts in so many threads, at so many sites, and the wording indicates that there is a common belief that every pc has a point, where if you install a GPU that is too much for it, the result would be a *decrease* in overall game performance.

So that is not the case, correct?

What I'm saying is that there is a GPU for each system that will allow the best performance for that system, and the next better performing GPU won't increase gaming performance, but it also not decrease it either, correct?

It would seem to me that all factors taken into consideration, the bottlenecking of a CPU should occur close to where the GPU runs at 100 percent, or the GPU should be the bottleneck close to the point where the CPU is running at 100 percent. Am I correct in assuming that this would represent the ideal CPU/GPU pairing?

Thanks.

D_Harris

 

[Kaamos_Llama]

OK. The reason for the question, which was difficult to word correctly, is I've read so many posts in so many threads, at so many sites, and the wording indicates that there is a common belief that every pc has a point, where if you install a GPU that is too much for it, the result would be a *decrease* in overall game performance.

So that is not the case, correct?

What I'm saying is that there is a GPU for each system that will allow the best performance for that system, and the next better performing GPU won't increase gaming performance, but it also not decrease it either, correct?

It would seem to me that all factors taken into consideration, the bottlenecking of a CPU should occur close to where the GPU runs at 100 percent, or the GPU should be the bottleneck close to the point where the CPU is running at 100 percent. Am I correct in assuming that this would represent the ideal CPU/GPU pairing?

Thanks.

D_Harris

Mostly correct yes. Performance will never decrease from having a faster card so long as everything else in the system supports the card as @Brian Boru was saying.

It would always be better to have a much more powerful CPU because then you can just keep buying new graphics cards and not lose performance to the CPU for years.

In practice though CPU's are limited by the speed on one core as well as the amount of cores. So in many cases a 6 core CPU could be faster for gaming than say an old 16 core CPU because its individual cores are faster. I think this is Amdahls law, cant remember exactly, if you wanted to look it up. At some point you are always limited by the speed of a single core, and throwing more cores at it doesnt help.

Where the limit is varies from game to game depending on the game type as well. Its impossible to be 100% GPU limited in all situations, but that would be ideal.

 

[Shiruken77]

Think of it this way in comparison to cars. Cheaper cars less performance high end exotic race cars more performance. Both can get you from point A to point B but one will get you there faster. Having a high end GPU wont affect performance UNLESS the hardware surrounding is mediocre then having a fast high end GPU wont perform at its best. Always consider the surrounding hardware MOBO, CPU, MEM, PSU, Storage etc and adjust GPU choice to maximize performance to cost. It wouldnt make sense to pay for the top of the line GPU while the system hardware is less than optimal.

 

[D_Harris]

It was difficult wording the original question, but I think Kaamos_Llama answered it.

Basically, every system theoretically can be paired with a card that is optimal for that system. If you are then given a higher performing card to replace it, it won't improve performance, but at the same time it will not drop system performance under that of the original card.

Like moving from the GTX 1650 Super to the higher performing GTX 1660.

Core i7-4790 and GeForce GTX 1650 SUPER build in General Tasks | Bottleneck calculation | PC Builds

Bottleneck calculation for Intel Core i7-4790 and NVIDIA GeForce GTX 1650 SUPER for General Tasks. Containing solutions how to resolve bottleneck.

pc-builds.com

Core i7-4790 and GeForce GTX 1660 build in General Tasks | Bottleneck calculation | PC Builds

Bottleneck calculation for Intel Core i7-4790 and NVIDIA GeForce GTX 1660 for General Tasks. Containing solutions how to resolve bottleneck.

pc-builds.com

Just because that site rates the specific system hardware as too weak for the GTX 1660, doesn't mean that the gaming performance itself will drop under that of the same hardware with the GTX 1650 Super installed.

Thanks.

D_Harris

 

[Kaamos_Llama]

Dont get to hung up on bottlenecks. Its something people new to the hobby worry about to much. Its always either on the CPU or GPU and it varies game by game, and even depending whats happening in the same game.

As long as you're getting smooth frame rates its doesn't matter where the 'bottleneck' is.