FSX not using full CPU power?

[AlexMD11 15]

I have recently upgraded to a new system that would allow me to play FSX (see specs in my signature). However, I still feel that performance is not what it should be and I really cannot find out what it is. Yesterday I noticed that when I opened up the task manager while running FSX, only one of the four cores (I have HT turned OFF) was at a 100% while the others were not; overall I was using like 50% of CPU power. Still, in the following setting, I could not manage to keep my framerate steady at 25 FPS, as it was in the upper teens:PMDG MD-11 at FSDreamteam's ZurichXREXWOAI Traffic @ 70%FPS Limiter set to 25 FPSI have used NickN's guide to tweak my FSX. Reducing traffic to 0% did not have a significant effect (difference of maybe 1 FPS). Therefore I have the feeling that they might be some other bottleneck.Still, could anyone explain to me why not more CPU power is used thus increasing FPS (with FSX being so CPU intensive) and if this is normal?Thanks,

[AlexMD11 15]

I have also checked my memory stuff in BIOS; it is on 8-8-8 or something like that. I read in NickN's tutorial that this is too high, but setting it to 6 makes that my computer won't start windows saying 'overclocking failed'. I don't have much experience in this field, so could anyone tell me how I can optimize my DRAM timings and whether this might positively affect performance?

[TechguyMaxC 516]

Unfortunately you can't simply change the timings of your RAM like that. RAM has to be designed to run at lower timings in order to do so. I doubt highly that memory latency is contributing to low FPS. Perhaps your expectations are simply too high. The performance you're experiencing doesn't sound out of line for the settings you're running.

[Mace 1,927]

/agree with TechMax.You are running one of the most detailed aircraft (MD-11) at one of the most detailed airport sceneries (Aerosoft Zurich) that you can find in FSX. If you are even approaching 18-20 fps on the ground there that is performance I would not mind having. You may want to experiment with framerate: unlimited (while on the ground, where you really get hit), or the fps_limiter program discussed here a while back.

[ryanbatc 12,857]

Agreed, watch that AI slider, if you downloaded a lot of WOAI packages reduce that slider to 45-50% - which should make a big difference. 70 is really high... maybe if it were default traffic - but WOAI places many more planes than default.

[AlexMD11 15]

Thanks for your replies! I will do some more testing with the FPSlimiter later today. I will also check traffic, since last time I did some experiments with that, I did not notice any significant difference in performance.

[GHarrall 494]

I have recently upgraded to a new system that would allow me to play FSX (see specs in my signature). However, I still feel that performance is not what it should be and I really cannot find out what it is. Yesterday I noticed that when I opened up the task manager while running FSX, only one of the four cores (I have HT turned OFF) was at a 100% while the others were not; overall I was using like 50% of CPU power. Still, in the following setting, I could not manage to keep my framerate steady at 25 FPS, as it was in the upper teens:PMDG MD-11 at FSDreamteam's ZurichXREXWOAI Traffic @ 70%FPS Limiter set to 25 FPSI have used NickN's guide to tweak my FSX. Reducing traffic to 0% did not have a significant effect (difference of maybe 1 FPS). Therefore I have the feeling that they might be some other bottleneck.Still, could anyone explain to me why not more CPU power is used thus increasing FPS (with FSX being so CPU intensive) and if this is normal?Thanks,

You will never see all four cores 100% loaded. FSX does utilise as many cores as you can throw at it but only to a certain degree. The extra cores are used for scenery threading.

[JimmiG 244]

You will never see all four cores 100% loaded. FSX does utilise as many cores as you can throw at it but only to a certain degree. The extra cores are used for scenery threading.

The same is true for any game or sim currently out. There will always be instructions that depend on the results of previous instructions which limits how much you can do in parallel across multiple cores or CPUs. Programmers of today have a much harder time than they did eight or ten years ago, when they could always count on AMD and Intel to double the clock speed every 1.5 years or so.As you say, FSX only uses the extra cores to speed up the scenery loading process, not to improve the actual frame rate. I have however found that with a quad-core or even a fast dual-core CPU, you can safely lower the Fiber Frame Fraction setting significantly, without introducing blurries. Try curring it in half at first, then again if the results are still good. This tends to free up a few CPU cycles to put towards raw frame rates, though the difference isn't very big.Also FPS in the high teens with complex scenery and aircraft has to be considered acceptable when you're talking about FSX. My Athlon X2 only managed single-digit frame rates, my previous Phenom X4 at 2.3 GHz managed maybe 12-13 FPS. Only my 3.2 GHz Phenom II manages frame rates about 20 with default aircraft and scenery at nearly maxed settings.

[gman! 1]

I was just about to say the same thing as everything else. I don't think I have ever seen any game that uses 100% of a CPU. Especially if it is a quad core. Maybe with a single core, it maybe just might hit 90+% but never 100% on multicore CPUs. If games were designed that way, you would not be able to switch tasks quickly, and instead of making games faster by using 100% it actually makes them slower at times because all the CPU cycles would be dedicated to one task... This is why people recommend putting in "AffinityMask=14" because it doesn't use the first CPU which the OS uses and with FSX using all 4 cores the 1st core would hit max often due to unorganized priorties and to many threads/processes on one core. Like others said, FSX process the main things such as physics and verification of scenery from other cores on the 1st core running FSX (not the 1st core on the CPU, but the 1st core set for FSX) then the rest process scenery. So if you ever see your CPU 100% on all cores expect lots of heat, a slow response, and an non-enjoyable experience...Put this anywhere in your FSX.CFG and see how FSX performs:"[JOBSCHEDULER]AffinityMask=14"also make sure"TEXTURE_BANDWIDTH_MULT" is less than 90. Some people don't understand how this tweak works, and then they recommend insane values. If you have it set higher or something like 400 some recommend, it will send textures to your GPU as if it were at 400FPS, if you lower it to the default like 40FPS it will send textures as if it were at 40FPS and spreads texture loading across more frames, than just at once with something high as 100. This decreases stuttering, may improve loading, and increases FPS. Also if you have the fiber_frame_time_fraction tweak remove that. The only things you should have are affinity mask, bufferpools, and texture_bandwidth_mult. Anymore and your running FSX against how it was made, and making it less efficient.Sorry, forgot to add Affintymask=14 sets FSX to the last 3 cores, which improves performance since the Windows OS and most other processes are set the main core (Core 0). Since FSX uses the 1st core its set to for physics processes, and scenery processed on other cores passes through the main FSX processing core, affinitymask=15, or no affinitymask tweak maybe detrimental to performance. The last 3 cores will have less process and FSX running on Core 1 (The 2nd core of the CPU will cause way less problems and most likely result in more performance and a more enjoyable experience!)

[AlexMD11 15]

Thanks all! It definately makes sense now that games don't use 100% CPU power. However, the bufferpool and affinitymask tweaks do not really seem to make a difference for me. I have been experimenting with these for a while now, but I still haven't found the . After some tweaking with traffic settings and the FPS limiter, flights are pretty smooth now despite some alt-tab / alt-enter issues. I guess that it will be best to just keep on tweaking the small details and hope for a flight experience that is as smooth as possible ;)

[Mace 1,927]

I have however found that with a quad-core or even a fast dual-core CPU, you can safely lower the Fiber Frame Fraction setting significantly, without introducing blurries.

Can someone confirm for me that FIBER_FRAME is meaningless for anything but single-core cpu's?I thought for sure Phil Taylor said it served no purpose on a dual or quad core machine, and in the last couple of weeks I've seen 3 or 4 people mention FIBER_FRAME and it's merits, and they had dual's and quads!

[Guest Mower]

You know, the company that can put out a decent flight sim that covers FSX and is PROPERLY CODED to fully leverage pc resources, will put this decrepid BROKEN FSX into the waste bin of history where it belongs.I find it utterly appalling that my rig cannot handle this sim.

[Guest FxF3]

You know, the company that can put out a decent flight sim that covers FSX and is PROPERLY CODED to fully leverage pc resources, will put this decrepid BROKEN FSX into the waste bin of history where it belongs.I find it utterly appalling that my rig cannot handle this sim.

I think MS shut down ACE's before they had time to fine tune FSX, with the new tech coming out after its release.Thats one reason I think people should just be happy with what they are getting in FPS instead of pumping money into a new system everytime a new cpu or gpu comes out more then likely FSX will still be around 5 years from now unless something big chances so wait at least every 2 years you will be much happier unless you have money to burn some in here do, I'm just not one of them :( .

[gman! 1]

I think MS shut down ACE's before they had time to fine tune FSX, with the new tech coming out after its release.Thats one reason I think people should just be happy with what they are getting in FPS instead of pumping money into a new system everytime a new cpu or gpu comes out more then likely FSX will still be around 5 years from now unless something big chances so wait at least every 2 years you will be much happier unless you have money to burn some in here do, I'm just not one of them :( .

Well said. I get more than 40 FPS most of the time so I'm very happy with it! As long as its smooth enough for you and is playable then you should enjoyable. Anything more than 15FPS with most add-ons is sufficient, its not like an FPS game. Even in Crysis I get more FPS but 15FPS in FSX and 15FPS in Crysis are two different things.

[Guest shinysuitman]

I was just about to say the same thing as everything else. I don't think I have ever seen any game that uses 100% of a CPU. Especially if it is a quad core. Maybe with a single core, it maybe just might hit 90+% but never 100% on multicore CPUs. If games were designed that way, you would not be able to switch tasks quickly, and instead of making games faster by using 100% it actually makes them slower at times because all the CPU cycles would be dedicated to one task... This is why people recommend putting in "AffinityMask=14" because it doesn't use the first CPU which the OS uses and with FSX using all 4 cores the 1st core would hit max often due to unorganized priorties and to many threads/processes on one core. Like others said, FSX process the main things such as physics and verification of scenery from other cores on the 1st core running FSX (not the 1st core on the CPU, but the 1st core set for FSX) then the rest process scenery. So if you ever see your CPU 100% on all cores expect lots of heat, a slow response, and an non-enjoyable experience...Put this anywhere in your FSX.CFG and see how FSX performs:"[JOBSCHEDULER]AffinityMask=14"also make sure"TEXTURE_BANDWIDTH_MULT" is less than 90. Some people don't understand how this tweak works, and then they recommend insane values. If you have it set higher or something like 400 some recommend, it will send textures to your GPU as if it were at 400FPS, if you lower it to the default like 40FPS it will send textures as if it were at 40FPS and spreads texture loading across more frames, than just at once with something high as 100. This decreases stuttering, may improve loading, and increases FPS. Also if you have the fiber_frame_time_fraction tweak remove that. The only things you should have are affinity mask, bufferpools, and texture_bandwidth_mult. Anymore and your running FSX against how it was made, and making it less efficient.Sorry, forgot to add Affintymask=14 sets FSX to the last 3 cores, which improves performance since the Windows OS and most other processes are set the main core (Core 0). Since FSX uses the 1st core its set to for physics processes, and scenery processed on other cores passes through the main FSX processing core, affinitymask=15, or no affinitymask tweak maybe detrimental to performance. The last 3 cores will have less process and FSX running on Core 1 (The 2nd core of the CPU will cause way less problems and most likely result in more performance and a more enjoyable experience!)

Thansk for the advice. I'll try it out.