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MD-11X and multiples cores

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Hi, I was wondering if the PMDG MD-11X is specifically coded to spread the CPU workload across multiple cores, or does that automatically occur since FSX itself uses multiple cores?Thanks,Craig

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I'm interested in knowing that as well, I'm about to buy a CPU and I would like to know whether I should go for the E8500 or Q9400. I was told that I'll get better framerates with the higher clock speed (3.16GHz) E8500, but will I get even more FPS with the MD-11 by going for a lower clock speed (2.66GHz) quad?

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If you're running FSX you have to go for Quad core with the highest clock speed you can afford. This is true whether you're flying PMDG aircraft or default aircraft. Reading CPU cores is solely down to the FS platform, not the addon.Dan.

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The problem is that I can only afford a Q9400, and reading from the other threads here in Avsim suggests that for FPS, a dual core with a higher clock speed will beat the quad with a lower clock speed. The only advantage of a quad is better loading of scenery. http://forums.avsim.net/dcboard.php?az=sho...&topic_id=42740So my question is how efficent is the MD-11's code with regards to quad core technology? e.g. Do I get so much more FPS with a quad that it completely negates the FPS advantage of higher clock speeds with the duo?BTW I won't be overclocking my CPU because I don't have space for a good aftermarket cooler.Best regards,

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Hi,Just as an FYI I don't suffer scenery load issues on my rig. Get SP2 installed, set the frame rate slider to Unlimited, and DO NOT tweak the FSX.cfg file manually, and you're good to go!Be realistic - you can NOT run this sim with all the sliders maxed. I've tried, and failed, and learned a few things in the process. If you want to try my FSX config, I can send you my FSX config save file (you need to load it up via the FSX GUI before you actually start flying).In another thread around here I posted screenshots of the sim to show that FSX can look good and run very well on even my kind of hardware (note that I intentionally went for DX9 optimized system, hence the 7950GX2). Your milage may vary, yada yada yada...Can FSX really benefit from quad cores for actually running the sim (forget loading things - seems quick enough on a dual core)? This is a question that needs a serious answer. I'm more than happy with my dual core for FS generally (I have other reasons for wanting a quad core that are not related to FS), but faster is better!IMHO get the fastest dual core you can, unless there is an exceptional reason to go for a quad (e.g. different/better/faster architecture). You might want to wait for the i7 due out Q2 next year.Best regards,Robin.

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Hi Robin,The reason I recommend Quad core for FSX is that I noticed a huge improvement going from a Core 2 Duo Extreme to a Quad Core Extreme whilst changing little else on my PC. Whilst my Core 2 Duo ran everything else on my PC fine I was still unhappy with my FSX performance and the Quad core upgrade has largely solved that.Cheers,Dan.

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>Hi Robin,>>The reason I recommend Quad core for FSX is that I noticed a>huge improvement going from a Core 2 Duo Extreme to a Quad>Core Extreme whilst changing little else on my PC. Whilst my>Core 2 Duo ran everything else on my PC fine I was still>unhappy with my FSX performance and the Quad core upgrade has>largely solved that.>>Cheers,>Dan.Now That's an answer!Any idea (in percentage) how much your frames improved sir?Concerning NOT tweaking the .cfg file: what's wrong with that? It can improve frames easily with 25% depending of other factors...Best Regards,Bert Van Bulck

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Hi Bert,Essentially I went from sparse autogen and using the FSX.cfg to turn down trees and buildings to dense autogen and still experienced a 50% increase in frame rates. I also get less stuttering and minimal blurring. FSX is tied to your CPU whilst running a pair of 8800GTXs (as I do) has little effect on FSX. I can't really comment on the clock speed theories (fast duo vs. slower quad) apart from my own experiences.I believe at weak you do need in the FSX.cfg is to get it to recognise the multiple cores although I could be wrong about that if others are better informed....Dan Parkin.

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You don't need anything special for the MD11... it is FSX that demands the CPU power. During early beta tests, I ran a P4 (1-core) and was happier with the MD11 than 747X. After that system died, I now have a home built Q9650 3GHz Quad (the extreme chips were double in price, this was less than $600 from newegg).. of course FSX is much more fluid. The surprising thing about the MD11 is how fluid the visuals are compared to the 747X. Very nice, even with the P4 CPU.FSX runs in all four cores, there is a cfg line that can be added too (affinity mask = 15 or something like that.. see Phil Taylors blog for specifics).

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>Hi Bert,>>Essentially I went from sparse autogen and using the FSX.cfg>to turn down trees and buildings to dense autogen and still>experienced a 50% increase in frame rates. I also get less>stuttering and minimal blurring. FSX is tied to your CPU>whilst running a pair of 8800GTXs (as I do) has little effect>on FSX. I can't really comment on the clock speed theories>(fast duo vs. slower quad) apart from my own experiences.>>I believe at weak you do need in the FSX.cfg is to get it to>recognise the multiple cores although I could be wrong about>that if others are better informed....>>Dan Parkin.Hi Sir,My question about NOT tweaking the .cfg was as response to someone other's post :)I fully agree with you that tweaking your .cfg file can improve frames dramatically (try the Fiber Frames Fraction and you will see :) )Best Regards,Bert.

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You should get the quad core because FSX itself will perform better. The MD-11 code does have some multithreaded elements in it, but the vast majority of your CPU time is going to FSX itself, not the panel.

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If you feed it, it will eat. This chart shows the MD running on a Q6600 at 3.6Ghz, 4Gs O ram and Vista 64. The CPU is Always using the equivalent of 2 cores and typically using 100% of all 4 cores.Notice the memory usage. Virtual Size is the op system scheduling projected ram usage. It's just a notepad, but if this goes over 2Gs on a 32bit op system, an OOM will occur. If the 32bit system had the 3G switch enabled, this can go to 3Gs. A 64bit system allows 4Gs. WS Private is physical ram usage. This airplane will run on a 32bit system with 2Gs of ram. That is not an issue. However for best performance, a 3G'd 32 bit system or a 64 bit system is best. However core speed and number of 'em will are still the big dogs. http://forums.avsim.net/user_files/193239.jpg

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