i5-4590 & Bottlenecking

[BigDay]

When will the i5-4590 start to bottleneck a GPU or x2 GPU's in SLI or CF? In other words, can you run a 980 ti or Titan X with this CPU?

 

Thanks broz!

[PlayStation 2]

i really wouldn't

[Tagiau]

It would perform the same as a non oc'd 4690k. Which I have no clue how well it does with crossfire. But it wont' have an issue with a 980ti. 

[Mohenjo]

sure, its not to bad. i mean you wont get the full power of the 980ti but youd still get a mega fuck ton 

[HumbleMobo]

When will the i5-4590 start to bottleneck a GPU or x2 GPU's in SLI or CF? In other words, can you run a 980 ti or Titan X with this CPU?

 

Thanks broz!

Think of it this way...i5 4590 will perform about the same as a 4790k with SLI or CF.  To put it into perspective, you get raped, one has a bigger dek, in this the Titan X, but then another one comes in and you weren't prepared.  See the bottom line is, I'm unsure if the i5 would be able to fully utilize the Titan-X's capabilities.  Now if you had a more reasonably sized dek, in this case the 980ti, it would be easier to handle and you'd be ready(maybe even excited) for a second.  So it's all dependent on the OC or OV

[KemoKa]

When will the i5-4590 start to bottleneck a GPU or x2 GPU's in SLI or CF? In other words, can you run a 980 ti or Titan X with this CPU?

 

Thanks broz!

Understand that bottlenecking is not a black/white concept, most processors hold back high-end GPUs to at least some extent. The question is how much your CPU will hold it back. admittedly if you have a recent Intel quad-core, it won't be by much. if you add hyperthreading, it'll be less, and if you overclock it, it'll be less than that. Eventually you'll reach a point where the GPU is not bound by the CPU at all and it can go crazy, but not all CPUs are capable of keeping up with flagship GPUs. AMD FX processors are prime examples of this. It also depends on the game. Some games like Arma and Minecraft are heavily CPU-bound, but others can go at full speed with whatever CPU.

[Hieb]

As always it would depend 100% on the specific game and settings you're playing at... are you looking for 1080P 144Hz gameplay? Then the i5-4590 will probably bottleneck in a lot of games, as at framerates that high there'd be tremendous CPU load. Looking at 4K 60 Hz gameplay? Then that CPU could drive that without any issues.

[BigDay]

As always it would depend 100% on the specific game and settings you're playing at... are you looking for 1080P 144Hz gameplay? Then the i5-4590 will probably bottleneck in a lot of games, as at framerates that high there'd be tremendous CPU load. Looking at 4K 60 Hz gameplay? Then that CPU could drive that without any issues.

 

interesting, i didn't realize that playing at over 60 fps would require more of an input from the cpu. how did you learn about this? i'd like to learn more.

[incarnate]

interesting, i didn't realize that playing at over 60 fps would require more of an input from the cpu. how did you learn about this? i'd like to learn more.

It comes down to how graphics are rendered. The cpu can only provide the gpu with so many instructions. This limits the max frame rate. You can see this yourself in any game on almost any hardware. Load up a game and set everything to low, then start taking down the resolution, eventually you'll pass a point where the cpu stats bottlenecking the graphics card. The graphics card can run the game at x framerate, but the cpu can't feed instructions to the gpu fast enough so the gpu starts waiting around. Lowering the resolution further yields the same framerate. Sometimes a cpu can support up to 300 fps in one game but another only 80, this all depends on how heavily the cpu is being used by the logic and other aspects of the game that require the cpu.

[Yoinkerman]

Its fine.

You're also misusing bottleneck.

[Inchun]

I don't think it'll necessarily bottleneck, rather the higher end cpus would perform much much better since they can fully utilize all that power in those cards.

[Hieb]

interesting, i didn't realize that playing at over 60 fps would require more of an input from the cpu. how did you learn about this? i'd like to learn more.

 

For every frame your video card renders, the CPU first has to do a bunch of processing for it... the CPU processes animations, where all the objects are and then tells the GPU. The CPU also processes a lot of effects... it's involved heavily in shadows, lighting and particle effects (like explosions). So the more complex all of these things become (or the less optimized a game is), the more work the CPU has to do for each frame. And because the CPU does this for every frame, each frame adds more CPU load. So playing at 30 FPS will have roughly half the CPU requirements of playing at 60 FPS (although in some games physics calculations, AI, etc. are not tied to framerate, so then the CPU usage doesn't scale linearly)

 

So higher settings and higher framerates means more things for the CPU to process...

 

So if a certain CPU reaches its limits at, let's say, 45 FPS at high settings @ 1080P in a game with a GTX 760, then that same CPU will also reach its limits at 45 FPS at high settings @ 4K with a GTX 980 Ti.

 

This is why I don't like people saying X CPU will bottleneck Y GPU, because it depends. An i5-6600K could bottleneck a GTX 980 Ti if someone is playing triple A titles at 1080P, looking for 144Hz gameplay... playing at ~144 FPS requires a lot of CPU in big titles. Meanwhile if someone is playing at 4K, a GTX 980 Ti could probably be supported without any issues by a high end i3 (like an i3-4360) or low end i5 (like an i5-4440), because framerates at 4K are gonna be targeted around 60 FPS, which isn't too terribly demanding.

 

This is also why often times you'll see low-resolution benchmarks in CPU tests (although this is less common now since ever since Tek Syndicate's video about the FX-8350 people bitch about "real world" benchmarks, which serve a different purpose... but I digress). Because as you lower the resolution, it makes it easier for the video card to pump out more frames, and this allows you to find the point where the CPU spends all of its time processing frames (and physics, etc.) and cannot handle anymore... and at this point lowering the resolution further or adding a better graphics card won't improve the FPS because the CPU has reached its limit.

 

So long story short:

 

- CPU processes things for each frame (basically prepares it for the GPU, telling it what to draw)

- Particle effects, lighting effects, shadows (and ambient occlusion) typically have significant CPU involvement

- Then the GPU builds the picture out of pixels

 

Higher settings = more CPU involvement per frame

More frames = more frequently needs CPU to prepare frames