Hello all,

 

I have an i7-975 Extreme CPU.

 

This morning, in re-reading Word Not Allowed's set-up guide, from his blog site, I revisited the issue of running FSX with the CPU set up with HyperThreading enabled within the BIOS, or not.

 

After about 20 different saved flights and situations within FSX, I have (for myself at least) concluded that FSX gives you faster and more consistent FPS's when in HyperThreading mode, than not. In fact, for my system, a more sustained FPS of around 7 FPS, than when HyperThreading is turned off!!!

 

Yes, I used in Job Scheduler, within my FSX.cfg, a setting of 14 for non HyperThreading, and a setting of 84 when having HyperThreading turned on via my BIOS.

 

I also found something else, that if you have a HyperThreading capable CPU, and have that featured disabled, that your total system reaction time is 25 percent slower. For example, after having finished with my FSX session, and having five programs running alongside FSX in my sessions, and... starting to shut down after I did drop  to the desktop, the time it took for W7 Ultimate to end and shut down those programs, or 'threads', was at least 25 percent slower than when I have always had HyperThreading enabled.

 

So....for me the bottom line observation is:

 

1.  If you ONLY have FSX running, that doesn't actually fully utilize HyperThreading in of itself as a stand-alone, and NO OTHER support programs running in tandem...then perhaps you might see a higher sustenance in FPS on your system. The fact is...that nobody today is merely running FSX and nothing else pre-started or running alongside/within it.  Those weather, shade,A.I.Smooth sessions, are separate programs that absolutely are being enhanced within their running/threads, that a HyperThreading enabled system is taking on and smoothing out.

 

With HyperThreading ENABLED, my FSX sessions, are faster, smoother, in every way, with my other support programs running within their threads.  

 

So, with my opinion on this knowingly opposed to some others on AVSIM, regarding whether you should have HyperThreading enabled when using FSX....the answer is an absolute, YES!  Yes, if you are running multi-programs when using it.  We all do...and HyperThreading technology is there to smooth things along.  

 

Just make sure if you have HyperThreading on, or decided to check out my observations on your own system, Put this section withing your FSX.cfg file. This is for HyperThreading on;

 

[JOBSCHEDULER]

AffinityMask=84 

 

 

Ses

But of course. The CPU can manage its free time better than anything else and optimize its core usage with HT.

 

Also, getting rid of the AffinityMask setting, uses less CPU resources and allows the simulator to run better without being forced to divide work.

 

I've said this numerous times and even mentioned it to Word Not Allowed, but he had the "fame and glory"... Who am i to contradict him

But of course. The CPU can manage its free time better than anything else and optimize its core usage with HT.

 

Also, getting rid of the AffinityMask setting, uses less CPU resources and allows the simulator to run better without being forced to divide work.

 

I've said this numerous times and even mentioned it to Word Not Allowed, but he had the "fame and glory"... Who am i to contradict him

Perhaps you misinterpreted my post...I did not infer that Word Not Allowed was either right or wrong, but only referenced his name and guide, as a result of re-reading, and re-visiting the issue for myself regarding his entry, that you either use a setting of 14 for no HT, or a setting of 84 with HT, and with having revisited this issue with HT, that for my system, using HT enhances the entire computer session, and not only FSX performance. This is not about Word Not Allowed, not about any one particular person, or organization, it's only whether the reader wants to try out the HT 'yes', or HT 'no' on their system after seeing what my experience as reported was.  Nothing to do with any person, or their opinion.  Only that I revisited this issue this morning, and have decided to keep HT on indefinitely. I will try another session with the [JobScheduler] entry totally removed and see if there is an A/B difference in that regard. I'll report that when I have the time.  Although, with that entry and the setting of 84 with HT enabled, I am right up there at the top cap of my 30 FPS for such as  Orbx, etc.

 

Mitch

Well I must now be satisfied.  I've felt trapped in HT since reading Word Not Allowed's guide cause my Gateway FX6860 system is set to HT and the BIOS does not include the feature to disable it.

Interesting observations. I've been playing around with hyper-threading over the past couple of weeks using two different CPU's and found that FSX behaves quite differently on both with HT on or off. The two CPU's I used were:

 

Intel i7 3920XM

Intel i7 820QM

 

I found that with HT on, the 820 had problems maintaining FPS and was not very smooth than with HT off. With HT off and using the last 3 cores, I was able to use do my test flight (Orbx KHQM - KPAE with the RealAir Legacy) with FPS in the high teens.

 

The 3920XM was a different ballgame. I tried the 920 config (HT off, last three cores) on the 3920 and FSX just did like it. I had a lot of stuttering and the FPS was not consistent. I turned HT on and using the last 3 cores, I was getting a consistent 20FPS or higher while being able to run slightly higher settings on my scenery sliders. This may have something to do with the better GPU (nVidia K2000m 2GB vs FX880M 1GB).

 

While my test was not very scientific, I do believe that for FSX responds differently to to different CPU's with HT on or off.

 

I'm going to try Namco's suggestion to leave the affinity mask out totally and see what happens on the XM.

Well I must now be satisfied.  I've felt trapped in HT since reading Word Not Allowed's guide cause my Gateway FX6860 system is set to HT and the BIOS does not include the feature to disable it.

I had that exact issue as well.  I just reported a few days ago that I flashed to the lastest BIOS for Alienware A11 on my Dell 730x...and with doing so, gave me the ability to finally turn HT either off, or keep it on.  With my original Dell BIOS 1.0.5,, as you, there was no way to turn it off...it came shipped as on.  This morning I turned it off...and found probably why the Dell folks wanted it kept on. It absolutely enhances the entire system, no matter what program, or programs you are running.  So...I am keeping it on...and as they say, lol; That`s...that!

 

Cheers,

 

Mitchèr

I have read in various forums that HT does not impact FSX performance that much in itself but having it on increases the CPU temp when overclocking.  Having it on reduces the amount of overclock you can achieve and that impacts FSX performance. I have not had time to confirm this with my own testing.

 

Ted