A question about CPU bottleneck when upgrading GPU

[coercitiv]

Guys, to share, this is the graphs I get on MSI AB when running the Hitman benchmark in DX 11 and DX 12. The GPU usage is much smoother in DX12 but the true fact is that I see lower average framerates with DX12 for whatever reason.

That's because Maxwell gets a performance hit when running DX12 with no CPU bottleneck, however that performance hit is offset and becomes performance boost once the CPU gets cornered. So you just have to decide: DX11 with higher average FPS and lower minimums, DX12 with slightly lower average FPS and considerably improved minimums where CPU would be strangled in DX11.

As for the 1060 that's coming to you, Pascal has improved DX12 support relative to Maxwell, so even with the same CPU you will notice improvements.

 

[Yuriman]

yes it would

When 100% CPU limited, no it would not. I didn't mean that GPU upgrades in general do not improve framerates.

 

[Yuriman]

I would also like to ask an additional question. Do in-game settings in general have zero impact on CPU usage, or do they? Stuff like AA, AO, shadows, draw distance, texture filtering etc. Were I to run a game a random AAA game at Ultra and then at Medium, should the CPU performance be consistent between the two, or will it improve at Medium settings?

And if these settings do make a difference, what are the ones that make the most difference to counter a a CPU bottleneck?

Simple hypothetical situation. Imagine at EPIC settings with a GTX 1080 I get ~100 fps in Overwatch. I am always limited by CPU. Were I to drop down to the MEDIUM preset, can I expect however little at least some improvement in my framerate due to less CPU bottleneck?

Most, if not all of these settings do not affect CPU usage.

 

[AtenRa]

When 100% CPU limited, no it would not. I didn't mean that GPU upgrades in general do not improve framerates.

Again, even if you are CPU limited changing to a faster GPU will gain you higher fps.

Total War : Attila

Athlon 750K + R9 285 = 12.03fps = CPU limited

Upgrading to GTX 980 will gain you 50% higher fps . You are still CPU limited but you gain fps from the faster dGPU.

GTAV

Athlon 750K + R9 285 = 29,67fps = CPU limited

Upgrading to GTX 980 will gain you 32% higher fps. You are still CPU limited but you gain fps from the faster dGPU.

For more,
http://www.anandtech.com/show/10436/amd-carrizo-tested-generational-deep-dive-athlon-x4-845

 

[TestKing123]

If you're CPU limited and upgrading to a better graphics cards results in faster framerates, then you weren't that CPU limited in the first place.

http://www.pcgamer.com/will-your-cpu-bottleneck-your-graphics-card/2/

* If the CPU load is maxed out at 100 percent across the board, the CPU needs to be upgraded first.
* If the CPU load is hovering between 70 percent and 100 percent, a video card upgrade will still offer an improvement, but the upgrade path is limited. Unless you plan on upgrading the CPU in the near future, avoid high-end video cards. A GeForce GTX 960 or Radeon R9 280 is about the most powerful card that should be considered.
* If the CPU load is below 70 percent most of the time, any video card upgrade will likely not be bottlenecked.

 

[Yuriman]

AtenRa, your benches are averages, and I doubt the CPU is pegged at 100% for the entire duration of the benchmark. Also, you're comparing an AMD and nVidia GPU - the driver overhead is different on these cards.

 

[hsjj3]

If you're CPU limited and upgrading to a better graphics cards results in faster framerates, then you weren't that CPU limited in the first place.

http://www.pcgamer.com/will-your-cpu-bottleneck-your-graphics-card/2/

* If the CPU load is maxed out at 100 percent across the board, the CPU needs to be upgraded first.
* If the CPU load is hovering between 70 percent and 100 percent, a video card upgrade will still offer an improvement, but the upgrade path is limited. Unless you plan on upgrading the CPU in the near future, avoid high-end video cards. A GeForce GTX 960 or Radeon R9 280 is about the most powerful card that should be considered.
* If the CPU load is below 70 percent most of the time, any video card upgrade will likely not be bottlenecked.

For most AAA games, it seems like CPU usage is about 70-80% at most on average, sometimes lesser. Hitman was the only one running consistently 90-100% on DX11, but about 80-95% under DX12.

It's very odd. I've played many recent games like Rise of the Tomb Raider, XCOM 2, TW3, MGS V, Gone to the Rapture, Mirror's Edge: Catalyst without any CPU bottlenecks whatsoever. Hitman doesn't seem CPU intensive at all, plus I am running on Medium preset so surely that takes some load away from the CPU.