What would you advice to set up the cpu in the bios, P-cores only or with E-cores, HT off/on?

What is the respective affinity setting? Is it good to just let P3D set it or can it be made better manually?

Thanks

Dan

Edited June 17, 20232 yr by blaunarwal

I have a similar setup as you Dan.   It comes down to Heat and how you displace that.  I have the 4090 video card and a 1200w Power Supply.  I leave everything in the Bios at default.  No need to overclock unless you have a very custom liquid cool system on all components.   I get smooth as butter results using Very Higy settings.   Of course LAX tax's the system or EGLL but still smooth.  Just my opinion...

I overclock the core to which I've assigned the main thread to 6.0 GHz (on a 13900KS), and the rest at 5.8.  I like the performance set up like that.

I have HT off, and the last bank of 4 E-cores turned off in the bios, and P3D runs with an affinity mask of 262143 (hex 0x03FFFF) which puts P3D on 18 of the 20 active cores, leaving the last two E-cores for ancillary stuff.

With HT on or all E-cores running it won't hold 6 GHz on the main thread much of the time due to thermal throttling.  It does take an extraordinary cooling effort to make this work--I have an aggressive water cooling loop (2 x 360mm deep radiators in series on a separate rack plumbed with 1/2" tubing, Laing D-5 pump running at 80%) in a room with an ambient temp of ~18 deg C year-round.

Generally, I think HT is a superfluous heat generator in the presence of so many physical cores, and shutting down unneeded E-cores frees up more cache for the other cores.  The 13900K has a lot of flexibility with its ability to overclock on a core-by-core basis.  It's not necessary to get really good results, but it is a fun and worthwhile undertaking if you're into that sort of thing.  Clearly I am.  😉

@markmasterson Yes, I agree, this cpu does not need overclocking, since it is already higher in regular mode than my overclocked i9700 which I could run at 4.8 GHz. It makes a lot of heat, also have the 1200 W psu but still the RTX3090, which seems to be enough so far. 

@Bob Scott I followed your suggestions and it looks promising yet. I have an aio cooler with 2x240 mm fans. The cpu is at 72 C during flight. Comparing to my old system, the 13900K needs much more cooling and the fans give me much more noise, though I have set them to a manual silent mode, only spinning up above 50 C. Maybe my aio is not the best. The case only allows 2 fans mounted on the roof. I have the pump on the boards pump plug, though the manual said to put it on cpu I think.

Overall so far I'm not very impressed by the progress from i9700 to i13900, which should be much more. To avoid stutters I need to reduce settings, use SimstarterNG to divide the world in several parts. I have some more headroom than with the i9700 but in general when the sim is using one core at 100% then it stutters with both cpus.

Edited June 18, 20232 yr by blaunarwal

5 hours ago, blaunarwal said:

I followed your suggestions and it looks promising yet. I have an aio cooler with 2x240 mm fans. The cpu is at 72 C during flight. Comparing to my old system, the 13900K needs much more cooling and the fans give me much more noise, though I have set them to a manual silent mode, only spinning up above 50 C. Maybe my aio is not the best. The case only allows 2 fans mounted on the roof. I have the pump on the boards pump plug, though the manual said to put it on cpu I think.

Overall so far I'm not very impressed by the progress from i9700 to i13900, which should be much more. To avoid stutters I need to reduce settings, use SimstarterNG to divide the world in several parts. I have some more headroom than with the i9700 but in general when the sim is using one core at 100% then it stutters with both cpus.

You're right about the effects of maxxing out the main thread core.  Maintaining some headroom where the main thread runs is paramount to avoid stuttering.  The best way I've found over many years using P3D is to limit the sim's frame production at the driver level--in my case through use of VSync and a 30Hz monitor.  Utilities like Rivatuner that allow you to cap frames at the driver level are supposed to work as well, though I haven't messed with them since I went with a native 30Hz, large-format 4K TV eight years ago.  If you cap frames in the sim rather than at the driver, it still does the work of generating as many frames as it can, keeping the main thread core needlessly saturated at near 100% utilization.

When I moved up to the 13900KS (from a 10900K) I adjusted CPU-intensive settings upwards while adhering to my objective of keeping average main thread utilization in the 70-80% range.  Still very smooth. 

I'm also a believer in fast RAM and plenty of cache--the fastest CPU on the planet still does nothing while it has to wait for data.

3 hours ago, Bob Scott said:

You're right about the effects of maxxing out the main thread core.  Maintaining some headroom where the main thread runs is paramount to avoid stuttering.  The best way I've found over many years using P3D is to limit the sim's I--in my case through use of VSync and a 30Hz monitor.  Utilities like Rivatuner that allow you to cap frames at the driver level are supposed to work as well, though I haven't messed with them since I went with a native 30Hz, large-format 4K TV eight years ago.  If you cap frames in the sim rather than at the driver, it still does the work of generating as many frames as it can, keeping the main thread core needlessly saturated at near 100% utilization.

When I moved up to the 13900KS (from a 10900K) I adjusted CPU-intensive settings upwards while adhering to my objective of keeping average main thread utilization in the 70-80% range.  Still very smooth. 

I'm also a believer in fast RAM and plenty of cache--the fastest CPU on the planet still does nothing while it has to wait for data.

I have a 60/100 Hz Monitor, so I can't limit with VSync. I checked if I get more headroom with external limiting with NVidia System Panel but it looks the same, like with internal limiter. I have 100% on core 1 in both cases. Is there any other way I could try to reduce frames on a driver level? How did you reduce load of the main core further?

I have 2x32 GB DDR5 RAM, 5600 MHz but my board lists only a tune mode for this RAM of 5400. I also have one XMP mode. Maybe that one takes 5600 but can't see that. Maybe another BIOS update before it's possible. I took this RAM, cause I read the CPU does not support faster speeds. I see you got the 7800 MHz. What is your knowledge about that?

About the noise I found a freeware/donationware called Fan Control V160, which is better than my Gigabyte board software, which just stopped showing the fans today. No message about it. It's just no longer there. So now I have good cooling and less noise with full control. 

Dan

52 minutes ago, blaunarwal said:

I have a 60/100 Hz Monitor, so I can't limit with VSync. I checked if I get more headroom with external limiting with NVidia System Panel but it looks the same, like with internal limiter. I have 100% on core 1 in both cases. Is there any other way I could try to reduce frames on a driver level? How did you reduce load of the main core further?

I have 2x32 GB DDR5 RAM, 5600 MHz but my board lists only a tune mode for this RAM of 5400. I also have one XMP mode. Maybe that one takes 5600 but can't see that. Maybe another BIOS update before it's possible. I took this RAM, cause I read the CPU does not support faster speeds. I see you got the 7800 MHz. What is your knowledge about that?

I know a lot of folks have used RTSS (included as part of MSI's Afterburner utility) to accomplish a low-level frame rate cap.  I can't speak to specifics there--time to resort to some black-belt level Google-Fu.

The GSkill 7800MHz RAM I built with was not listed on the ASUS TVL for my mobo when I bought it (based on my good experiences with GSkill RAM in the past).  At first it would not run faster than 7200 MHz.  An ASUS BIOS update that appeared a few weeks after I built the machine made all the difference in getting it running at full XMP-rated speed (7800 MHz @ CAS 36).  The TVL only contains a relative few officially-tested RAM kits--it's woefully incomplete.  Some element of succeeding involves trial-and-error with timings, speeds, and voltages, and some of it is just pure luck in the silicon lottery.