Single Thread Performance

[LukeSutton]

Hey all,

 

Signed up for a bit of help around understanding single core performance with regards to gaming. I've recently started taking iRacing more seriously and I've been doing some benchmarking / working on performance.Information around getting iracing running nicely seems fairly sparse, so here's how I understand it at the moment. Iracing runs on DX11 and relies heavily on CPU performance. It uses only 2 threads, 1 for physics, and 1 for render.  Iracing has a metrics window which shows render times for the CPU and GPU, so you can see what is the bottleneck. I've balanced my settings so that the GPU bottlenecks in offline practice, but online as the amount of cars increases it swings to CPU bound.

 

My system is 3x 1080P 144hz  freesync monitors, i7 6700K, 1660 super, 16gb RAM. I have overclocked the CPU to 4.7ghz with hyperthreading disabled. Using passmark, I'm finding my single thread pace is on par with high end 9th gen processors.

 

 

My question here is, do I really have an upgrade path? Most races I'm hanging around 90 FPS. I realize I've probably oversimplified this too much, so I'm hoping someone can help me understand better. Would I be right in saying that upgrading to an AMD processor with say 32 threads would give no benefit as I would only use 2 of them, leaving 30 other threads idle?

 

Thanks in advance, Luke.

[Demonic Donut]

12 minutes ago, LukeSutton said:

Hey all,

 

Signed up for a bit of help around understanding single core performance with regards to gaming. I've recently started taking iRacing more seriously and I've been doing some benchmarking / working on performance.Information around getting iracing running nicely seems fairly sparse, so here's how I understand it at the moment. Iracing runs on DX11 and relies heavily on CPU performance. It uses only 2 threads, 1 for physics, and 1 for render.  Iracing has a metrics window which shows render times for the CPU and GPU, so you can see what is the bottleneck. I've balanced my settings so that the GPU bottlenecks in offline practice, but online as the amount of cars increases it swings to CPU bound.

 

My system is 3x 1080P 144hz  freesync monitors, i7 6700K, 1660 super, 16gb RAM. I have overclocked the CPU to 4.7ghz with hyperthreading disabled. Using passmark, I'm finding my single thread pace is on par with high end 9th gen processors.

 

 

My question here is, do I really have an upgrade path? Most races I'm hanging around 90 FPS. I realize I've probably oversimplified this too much, so I'm hoping someone can help me understand better. Would I be right in saying that upgrading to an AMD processor with say 32 threads would give no benefit as I would only use 2 of them, leaving 30 other threads idle?

 

Thanks in advance, Luke.

With higher IPC, AMD CPUs will do better at the same clock speeds vs Intel. But Intel always edges out the clock speeds over Intel, so they usually win at single thread performance.

 

Yes, a 32 core isn't going to be a benefit.  But a ryzen 3700x would still likely outperform your current CPU. However a 9900K will outdo the Ryzen chip.

 

For the most part, if all you care about is iracing performance, get the fastest clocked chip you can afford. With the best cooler and crank that OC up.

 

BUT if you are ok waiting a bit, see what the new Ryzen chips are when they release soon before purchasing.

[Guest]

1 thread game engine

1 thread physics

1 gpu for render.

Passmark with a grain of salt. Your 6700K has about the same epeen as a 3600X (give or take coule percent)

 

Can't view the pictures. 

 

Yes. your upgrade path would be current gen Intel or wait till later this year when AMD releases Zen3 or Zen2+ or what ever the 7nm+ refresh is gonna be. 4000 sreies I think will have some better IPC and higher base and boost clocks. Should be some good processors released later this year for sure.

[LukeSutton]

Yeah I'm happy to wait, Ideally I'd like to go from ~90fps to 150+. Is a 160% performance improvement attainable with any CPU? Should I just try to push this overclock a little harder for smaller gains?

 

iRacing is all I'm worried about here, nothing else I use this PC for is bottle necked by the CPU.

[LukeSutton]

Screenshot

[Guest]

Just now, LukeSutton said:

Yeah I'm happy to wait, Ideally I'd like to go from ~90fps to 150+. Is a 160% performance improvement attainable with any CPU? Should I just try to push this overclock a little harder for smaller gains?

Increase Cache frequency if you have happy cpu frequency

[Hairless Monkey]

Maybe delid your 6700K? Liquid metal that ish? My old 4790K is running happily at 4.8GHz in my wife's PC. Could push it further but I was prioritizing stability and simplicity on that one...

 

It's a fun little project at least.

[LukeSutton]

delid :S Don't know if I'm up for that. I suppose what I'm wanting to understand mostly is if these statements are roughly correct:

• My OC'd 6700k will give me basically the same frame rate as a stock 9900K based on passmark results. (grain of salt I know)
• Because iRacing only uses 2 (maybe 3) threads, single thread performance is the ONLY important metric? (only considering 4 core+ CPUs)
• No current stock CPU will really give any significant frame rate improvement.

[Guest]

43 minutes ago, LukeSutton said:

delid Don't know if I'm up for that. I suppose what I'm wanting to understand mostly is if these statements are roughly correct:

• My OC'd 6700k will give me basically the same frame rate as a stock 9900K based on passmark results. (grain of salt I know)
• Because iRacing only uses 2 (maybe 3) threads, single thread performance is the ONLY important metric? (only considering 4 core+ CPUs)
• No current stock CPU will really give any significant frame rate improvement.

Well let's say the 9900K is about 20% faster per core IPC (stock vs stock) 

 

That's a 20% figure rating looking at the

9900K with a 3.6ghz base clock 4.9ghz single core turbo

6700K with a 4.0ghz base clock and 4.8ghz single core turbo

+

10900K with a 3.7ghz base clock and a 5.3ghz single core turbo (closer to 30% faster) 

 

Thinking you are not quite catching current gen IPC.

You definitely and probably won't be able to shell out the memory frequency to do so.

Close maybe. If you had 5ghz stable, you'd be where you want to be. Can you do it?

[LukeSutton]

4 hours ago, ShrimpBrime said:

Well let's say the 9900K is about 20% faster per core IPC (stock vs stock) 

 

That's a 20% figure rating looking at the

9900K with a 3.6ghz base clock 4.9ghz single core turbo

6700K with a 4.0ghz base clock and 4.8ghz single core turbo

+

10900K with a 3.7ghz base clock and a 5.3ghz single core turbo (closer to 30% faster) 

 

Thinking you are not quite catching current gen IPC.

You definitely and probably won't be able to shell out the memory frequency to do so.

Close maybe. If you had 5ghz stable, you'd be where you want to be. Can you do it?

Got it to 4840mhz. Is it stable? No, it crashes in realbench, and it thermal throttles in cinebench. But it doesn't do either of those things in iRacing, Cubase, or DaVinci Resolve... so far... soooooooo lets go with that for now.

 

 4841.5mhz 110mhz x44. 1.26-1.452 volts

 

99th percentile CPU mark with 3085 single threaded score.

[LukeSutton]

Hmmmm, might this be more stable with a fixed voltage rather than the dynamic thing?

[Hairless Monkey]

8 hours ago, LukeSutton said:

delid Don't know if I'm up for that.

 

2 hours ago, LukeSutton said:

Got it to 4840mhz. Is it stable? No, it crashes in realbench, and it thermal throttles in cinebench.

Seems like you would really benefit from delidding, considering you are pushing your OC so far. It really is much easier than you think, although certainly nerve wracking the first time. The results can be very impressive, I got a 20C reduction in heat at the same settings on a 4790K that I delidded. Was able to take it from 4.6GHz all-core to per-core 5.0, 4.9, 4.8, 4.8, and it still runs cooler than before.

 

Aside from that, what kind of CPU cooler are you using? What kind of thermal paste? Upgrading to a beefy Noctua cooler or a 280mm/360mm AIO and I high-end thermal compound like Kryonaut could help.

 

Also see if you can OC your RAM a bit. That could help net you a few frames.

 

If you did all or some of that you'd be really close to 9900K performance for single thread. You already are pretty close.

9 hours ago, LukeSutton said:

Is a 160% performance improvement attainable with any CPU?

No. Single thread performance has not come that far since 6700K. I doubt it will for some time.

[LukeSutton]

31 minutes ago, HairlessMonkeyBoy said:

 

Seems like you would really benefit from delidding, considering you are pushing your OC so far. It really is much easier than you think, although certainly nerve wracking the first time. The results can be very impressive, I got a 20C reduction in heat at the same settings on a 4790K that I delidded. Was able to take it from 4.6GHz all-core to per-core 5.0, 4.9, 4.8, 4.8, and it still runs cooler than before.

 

Aside from that, what kind of CPU cooler are you using? What kind of thermal paste? Upgrading to a beefy Noctua cooler or a 280mm/360mm AIO and I high-end thermal compound like Kryonaut could help.

 

Also see if you can OC your RAM a bit. That could help net you a few frames.

 

If you did all or some of that you'd be really close to 9900K performance for single thread. You already are pretty close.

No. Single thread performance has not come that far since 6700K. I doubt it will for some time.

I'm running a Noctua L12: https://www.youtube.com/watch?v=5bHWrE6zL2E

Maybe I'll look into delidding. I have no idea what compound I'm using. I think something very generic when I installed it in... oh... I think the thermal compound is probably 5 years old. I don't recall having ever replaced it :S. 

 

Ram is up a smidge from 2133mhz to 2346mhz with the BCLK boost.

 

I should do this properly shouldn't I? I'd be pretty pissed if I lost work on Cubase through a dodgy overclock.

[jones177]

My computers are mainly for modding old single core/ thread games. All of them are CPU bound even at 4k. Somes are unplayable on a i7 6700k and some play just fine.

 

I did use a i7 8700k for a while and it did run modern games a lot smoother than the i7 6700k to the point that I did not want to play on the i7 6700k rig at all. It was not about the frames. I retired the i7 8700k because it could not compete with a 5ghz Intel CPU since it could only clock up to 4.9ghz.  It was fine paired with a GTX 1080 ti but with a RTX 2080 ti it was crushed.

 

Your upgrade path now is any 5ghz Intel CPU. 

Since you have waited this long I also recommend waiting for Ryzen 3. It may be a game changer. 

 

I will be getting a i9 10900k. Mainly because it sounds like fun. I did get an i9 9900k but it was not and upgrade so the rig went to my Son.

[Hairless Monkey]

15 minutes ago, LukeSutton said:

I'm running a Noctua L12

 

 

https://noctua.at/en/cpu/Intel_Core_i7-6700K

Quote

     compatible without turbo/overclocking headroom

 

 

https://noctua.at/en/nh-l12/specification

Quote

Notes and warnings

 

The NH-L12 is a low-profile quiet cooler designed for use in small form factor cases and HTPC environments. While it provides first rate performance in its class, it is not suitable for overclocking and should be used with care on CPUs with more than 95W TDP (Thermal Design Power). Please consult our CPU compatibility list and TDP guidelines to find out whether the NH-L12 is recommended for your CPU.

 

[LukeSutton]

8 hours ago, HairlessMonkeyBoy said:

 

 

https://noctua.at/en/cpu/Intel_Core_i7-6700K

 

 

https://noctua.at/en/nh-l12/specification

 

*Spits Coffee* Ah, I see.

 

Right then, here's the plan. I only need performance for iRacing, so I'm going to stress test on that. I'm reasonably confident temps won't venture past 75 degrees.

 

Then I'll set up another profile in the bios for everything else, base clock or just above.

 

Might splurge on some thermal paste.

[Hairless Monkey]

Lol. Sounds like a fine plan.