i9 13900K

[severniae 78]

Hi all,

I have a 13900K - recent rebuild. Don't even need to overclock on these new cores as it's already 5.5ghz out the box!

Question, in the old days we always used to set affinity masks - I was never certain if it actually did anything or was mere placebo as I tried with and without and rarely saw a difference.

What is the recommendation? And what AM should there be for a 13900k? I looked at the affinity mask calculator but it just seems to refer to physical and logical cores but doesn't seem to cater for the scores?

Help required!

Thanks,

James

[rickjake 243]

I also have a 13900K.   I don't bother with affinity masks.  I never really seen a difference when I did play around with it.  I think its better to just let windows decide what's best,  in my opinion. 

[Bob Scott 7,721]

With HT off, an AM isn't really necessary.  Since the 13900K allows per-core HT control, you can also turn HT off just on the core that runs the main thread (assignable in the config file), and that also will address the major issue that an AM will prevent, which is sharing of the main thread's core with other processes on it's paired virtual HT processor. 

I have my 13900KS overclocked to 6 GHz on one core (main thread assigned to that one), HT completely off, one block of 4 e-cores disabled in BIOS to reduce power demand/heat, and an AM that blocks P3D from using the last couple of e-cores, which are kept active and available for other processes.  The improvement over running stock is marginal and not strictly needed--the CPU is still a rock star at stock speeds.  That said, tinkering with and optimizing the config can be rewarding in its own right.

[cowpatz 243]

21 hours ago, Bob Scott said:

 

I have my 13900KS overclocked to 6 GHz on one core (main thread assigned to that one), HT completely off, one block of 4 e-cores disabled in BIOS to reduce power demand/heat, and an AM that blocks P3D from using the last couple of e-cores, which are kept active and available for other processes.  The improvement over running stock is marginal and not strictly needed--the CPU is still a rock star at stock speeds.  That said, tinkering with and optimizing the config can be rewarding in its own right.

Bob, does the blocking off of the 4 e-cores reduce the heat/power by much? I always find it alarming the temps these that these CPUs produce (even with water cooling). 

[Ray Proudfoot 8,963]

Just to add my six penneth. I also have an i9-13900K running at the stock 5.5Ghz.

Running P3D v5.3HF2 with a 4090 at 4K could be considered to be pushing things pretty hard. But with a 30Hz monitor and VSync the CPU isn’t working flat out most of the tine.

The exceptions are at really busy airports with lots of Ai. But once airborne 30 is easily maintained meaning the CPU isn’t working hard so temps remain reasonable.

So the biggest way of controlling temps is running at 30, not flat out.

I have disabled HT and have 24 VPs available. My AM uses 2, 4 and 6 for the three primary processes. I avoid 0 as the OS can use it.

[Bob Scott 7,721]

3 hours ago, cowpatz said:

Bob, does the blocking off of the 4 e-cores reduce the heat/power by much? I always find it alarming the temps these that these CPUs produce (even with water cooling). 

Not a lot, but it made enough of a difference to keep that one golden core that runs my P3D main thread stable at 6 GHz.

A 13900K/14900K running at stock speeds is still very, very fast and will rock P3D with CPU package power averaging around the 100-120W range.  When you overclock all those cores, power demand and heat production goes up rapidly, requiring an aggressive cooling solution.  The 12th gen and later Intel CPUs allow for some interesting partial-overclock scenarios, as well as dynamic clock bumping on select cores based on power/temp thresholds.