A question regarding clock speed

[shally17 1]

Hello All,

I currently have an old i7 3770 overclocked to 4.2. If I get an i7 9700 and overclock it to 4.9 this represents an increase in clockspeed of around 17%. My question is this. All other things being equal does this increase the framerate in the 2 major sims by around the same 17% or will the newer technology of the latest CPUs give an even greater increase? I hope this is not a stupid question!

Regards,

Steve Shallcross.

[Bob Scott 7,720]

This answer presumes you're using P3D and not XPlane or FSX.

You'll see more than 17% better CPU throughput as the result of five CPU generations worth of improvements in IPC (instructions executed per clock cycle) performance, but that doesn't necessarily translate into the same increase in frame rate, because there may be limitations driven by your GPU, memory performance, storage etc.

You also are doubling the number of physical cores, which will dramatically reduce the likelihood of frame rate slowdowns driven by terrain and texture loading over what you're seeing on a quad-core 3770.

So if your question is whether you should expect to see a significant performance increase, the answer is yes you should.  How much depends on how balanced the rest of the system is.

Regards

[stans 702]

I think w6kd pretty well summed up the effects of such an upgrade. 

[vortex681 806]

6 hours ago, w6kd said:

You'll see more than 17% better CPU throughput as the result of five CPU generations worth of improvements in IPC (instructions executed per clock cycle) performance

But, perhaps, not too much more than 17%. If you're talking about raw, clock-for-clock, single thread performance then nothing has changed that much over those generations. Scroll down to the IPC/Single thread chart here: https://www.guru3d.com/articles_pages/intel_core_i9_9900k_processor_review,7.html

The latest CPUs tend to have higher base and turbo frequencies which give better performance in flight sims and newer chipsets and faster memory also each add a little to that performance increase. But for anything still relying predominantly on single core performance (like most flight sims), assuming that nothing else is causing a bottleneck, it's unlikely that you'd see massive gains over many older CPUs with a similar clock speed. It's the fact that the latest CPUs are able to reach higher clock speeds, rather than the fact that they have more cores, that make them more attractive in this genre. That's the real reason, in my opinion, why AMD processors seem to have been less popular with flight sim enthusiasts.

Edited May 23, 2019 by vortex681

[westman 257]

38 minutes ago, vortex681 said:

But, perhaps, not too much more than 17%. If you're talking about raw, clock-for-clock, single thread performance then nothing has changed that much over those generations. Scroll down to the IPC/Single thread chart here: https://www.guru3d.com/articles_pages/intel_core_i9_9900k_processor_review,7.html

 

15% to a Haswell 4790k the 3770k  was if i in the 10% range to the 4790k if i remember right  approx 20-25% is realistic and 10% higer clock  30-35% gain is possible.

I see a almost 50% over my base cpu 4790k 4.8ghz with 2400mhz cl 9 mems , to the 5.5ghz  9900k 4133 c16, both cpus tested in P3D 4.5 same gpu 2080Ti

Edited May 23, 2019 by westman

[Bob Scott 7,720]

4 hours ago, vortex681 said:

But, perhaps, not too much more than 17%. If you're talking about raw, clock-for-clock, single thread performance then nothing has changed that much over those generations. Scroll down to the IPC/Single thread chart here: https://www.guru3d.com/articles_pages/intel_core_i9_9900k_processor_review,7.html

I think you need to go back and look at that chart again.  The IPC chart only extends back to the 4790K, which was, as Haase mentions, at least a ~15% improvement in IPC over the 3770k--improved IPC was one of the major benefits of Haswell over Sandy/Ivy Bridge.  See https://www.overclockers.com/forums/showthread.php/774429-Sandy-Ivy-Haswell-Broadwell-Skylake-IPC  On the chart you reference, from the 4790k to the 9700k, there's a 14.2% improvement in IPC, and from the 3770k to the 9700k it's more like a 34% increase in IPC...over a third more instructions executed per clock cycle.  Add that to clock speeds that are 20% higher, and that to a doubling in physical core count, and it's a major, major increase in throughput.

The data you yourself reference doesn't support a conclusion that w/r/t "...raw, clock-for-clock, single thread performance then nothing has changed that much over those generations."  

Regards

[vortex681 806]

1 hour ago, w6kd said:

I think you need to go back and look at that chart again.  The IPC chart only extends back to the 4790K

I wasn't specifically talking about the 3770k, You mentioned that you thought that there was "better CPU throughput as the result of five CPU generations worth of improvements in IPC" and I was replying generally about how the IPC hasn't actually changed that much over a number of generations. I still don't think that a 14% improvement in IPC (from the chart) over several generations of CPU is that impressive.

Edited May 23, 2019 by vortex681

[Bob Scott 7,720]

Maybe not "impressive", but certainly significant, especially as a multiplier combined with the clock speed increases over those generations.

My recent upgrade path was 2600k -> 4790k -> 7700k -> 8086k, and each step was a marked improvement over the one before it...the improvement gained by transitioning from Ivy Bridge to Coffee Lake Refresh in one step as the OP proposes would be nothing short of eye-watering.

Regards