Simviation Forums

After reviewing the docs on i7 and looking at the tech information at FSINSIDER I have come to the conclusion that there MAY BE some value in running HT with i7 and FSX if the affinity mask edit is used


I personally do not have time to drop what I am doing and go into this and test it correctly .. therefore I am going to post this for people using i7 to try


NOTE: IF you are running 4GHz and enabling HT may push the temp of the i7 processor over the 80c limit you should reduce the clock on the processor to ensure safe operation. You may wish to stress test with HT enabled and establish your clock first before running this test.


Enter the BIOS and ENABLE this setting if it is not already enabled:

Intel HT Technology


In the FSX.cfg add the following if it is not already there

[JOBSCHEDULER]
AffinityMask=N


use these settings for N as you test and you must EXIT the sim and relaunch between changes

255 - all 8 in use

254 - 7 in use with the first remaining free

252 - 6 in use with the first entire CORE remaining free

127 - 7 in use with the last remaining free

63 - 6 in use with the last entire CORE remaining free


Verify the use and the perf then report back please.


There are some unanswered questions about the JOBSCHEDULER and what I posted in affinity mask settings above with i7 would answer a lot of them.

Hi Nick,

I will prepare a proper test results/conclusion report later today; discovered something interesting last night. 920 OC 3.8(4.0 was unstable), 1600 RAM(7-8-7-7-20). TWO cores, HT on, locked 28, 8SxQ, Affinitymask=255, two stock planes + one add-on and very smooth even in turns. Bufferpool=70000000, never have been able to use that entry. TBM=80. Max temp in FSX=63C. OCCT running now and max seen was 60C.

Later.

Jack

Test Results.

JOBSCHEDULER test in FSX

1. System:       i7 920 OC to 3.8 Gh
     3Gb Mushkin tri-channel DDR3 7-8-7-20@1603
           

TWO cores <----  what is this.. I am not seeing this in my BIOS

Sorry for the delay, I was still testing.

Advanced
Intel(R) HT Technology
Active Processor Cores[All]  - default

I have the choice of 1,2,4,all.

Jack

[quote]Sorry for the delay, I was still testing.

Advanced
Intel(R) HT Technology
Active Processor Cores[All]

OK, thanks. I was slightly mistaken; the P6T manual: "Allows you to choose the number of CPU cores to activate in each processor package.
Configuration options:[All],[1],[2]"

Doesn't explain exactly what this means so I elected to gice it a try.

Jack

Opps, give it a try.

J

All,

Based on what Nick pointed out, my test is flawed! (I cut out 1/2 of my processing power, DUH). I went back to where I was supposed to be (All) and reran the test.

My experience I believe is smoother with Affinity mask=255, any other setting on my system resulted in frames jumping all around when locked at 28. The 255 setting was definitely the best for what I have.

Live and learn I guess.  Thanks Nick for the correction.

Sooner or later, I will get this fun stuff.

My temps maxed at 72C while in FSX with HT on so I was getting close even at 3.8Gh.

Jack

OK, that makes sense

So what you are saying is using the affinity mask for all 8 cores you see better results than running with HT DISABLED in the BIOS (all cores in use) and no tweak in the config?

I assume this is just a smoother flight and not one that produces higher frames..  

At the same time, have you tried maxing the Scenery Complexity and the Autogen slider to see what happens in both cases, HT ON and OFF?

Yes and No. Smoother flight with HT but I failed to try maxed with HT off but believe I remember that I had a micro-stutter flight with auto maxed and HT off.

Also found that the aircraft does, as you have said, make a difference.

When I changed from the 260 to the 172 over NYC at night, the ride was more fluid.

I'm hopeful someone else will come aboard with test results so you have vaild data points, especially with a 940 or 965.

Jack

PS why would ASUS offer a choice of cores?

There can be several reasons for that which are tied back to the new i7 internal system called 'uncore'

When I get my mobo back I will be onboard this test and let you know. I'm running a 240 and will be running 3.5-4 ghz

Nick,

Final Conclusion: after much thought, to give you as valid a data point as possible, I removed FSX, degragged, reinstalled FSX+Accel, used UTXUS, GEXn,some textures from REX, FSG.

On my system I cannot get unlimited without choppy flight, so I used locked 30 or 22 with the bufferpool entry, auto at 3/4, scenery@100.

My smoothest flight is with HT off and four cores@ 3.8.

I did use your test flt at SEA once + flights around DC and RIC with various weather settings.

Hope this helped.

Jack

Thanks Jack!

Absolutely it helps.. !