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Guest Steven Stratton

FSX Performance Issues Solved. Really.

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Of course at least a year before the 1000 GHz CPU hits the market, there'll be a version of flight sim that requires a 2000 GHz processor. :( R-

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When that happens, Microsoft will finally have the ability to get back in the game, probably using a bunch of high school kids and Quickbasic. And "cloud computing" will be just that. Up in the fog of the clouds.... forever.... :( Bob - Las Cuces NM.

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Unfortunately that does not solve the 2nd real problem which is the saturation of the reserved bandwidth for the PCIe buss for autogen.. that is where the major bottleneck is and the problem goes back to the design of FSX. FS9 has a max limit of 500 objects per tile. The tiles grew 4x in FSX and instead of the AG limit remaining in line with that they increased it 10+ times the FS9 limit which was not only silly it was a very poor decision based on the hardware at the time.When the Vsync issue was introduced in SP1 whereby stammer in smooth flight is seen it made tuning a smooth experience that much more difficult. Unfortunately the way the app works using the autogen restriction lines in the FSX.cfg file makes for very bad mojo on thread collisions The application posted in this thread actually combats the problem to a certain extent and is probably the best thing to hit the FSX world.. http://forums1.avsim.net/index.php?s=&...t&p=1551461The large memory (1GB) single core 280-285 Nvidia video cards can get smoother perf by increasing bufferpools to 400-490MB not because that amount is needed for FSX but because that will DROP the latency at the driver level on the PCIe buss giving it higher priority to the system for FSX AG. ATi x2 and the 295 Nvidia cards are useless for that tweak (or FSX for that matter) as the 2nd core and memory will not be addressed by FSXWe designed GEX Europe to be in line with hardware standards for autogen and also managed to resolve part of the perf problem around large pine forests in FSX which will effect the sim perf world wide when it is installed.None the less, I don't care how much CPU power the app gets.. FSX is basically a year 2000 triangle rendering engine that will unfortunately never catch up to the shader engine based graphic card designs now in use. In reality the wildly un-optimized design for memory access and thread management gives the user the impression a 5GHz processor will fix all their troubles when the fact of the matter is the application will be just as erratic on 5GHz as it will be on 4, or 3. The difference that is seen as CPU speed increases is not becuse the app needs that CPU power.. its because the lousy way the app address the system it needs that power to visually overcome what I consider the wasted resources and poor memory/cpu access of the design.

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I'm fascinated with Nick's explanation, as it makes a lot of sense to me. I've just gone from a Core 2 duo E6700 to a Core i7 920 overclocked to 3.2 GHz and the improvement in FSX performance is not nearly as good as the hardware jump should have given me. But this could be related to my GPU, an ATI 4870 that just does not seem to like FSX. I've only just found a way to get VSync on under Windows 7, as this simply doesn't work with the Catalyst drivers under Vista or W7. Seems there's a utility bundled with RivaTuner that does the job. Works a treat!Nick, should the ATI 4870 benefit from the buffer pools tweak? I've already tried it but there does not seem to be any useful improvement at the settings I've tried so far. Is it worth trying more settings or an I just wasting my time?Cheers,Noel.

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I'm fascinated with Nick's explanation, as it makes a lot of sense to me. I've just gone from a Core 2 duo E6700 to a Core i7 920 overclocked to 3.2 GHz and the improvement in FSX performance is not nearly as good as the hardware jump should have given me. But this could be related to my GPU, an ATI 4870 that just does not seem to like FSX. I've only just found a way to get VSync on under Windows 7, as this simply doesn't work with the Catalyst drivers under Vista or W7. Seems there's a utility bundled with RivaTuner that does the job. Works a treat!Nick, should the ATI 4870 benefit from the buffer pools tweak? I've already tried it but there does not seem to be any useful improvement at the settings I've tried so far. Is it worth trying more settings or an I just wasting my time?Cheers,Noel.
Tuning list is quite clear... 512MB cards will probably not see any advantage to increasing bufferpools as the amount needed to make any dent in the situation is about 25-35MB+ and that means 512 cards lose that video memory to rendering other things. FSX wants 512MB if it can have it and bufferpools is over and above that amount. So cards that only have 512MB of memory available are really not suited to use the tweak at all640 cards, max 35MB768 cards, max 70MB1GB cards, max 450-490MBall others should leave the tweak out of the configand yes, a Nvidia 285 upgrade would be more in line with a i7 system for what FSX needs

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Thanks for your reply Nick! If it's just the video card memory I should keep trying the bufferpools tweak, as the card I have is a PowerColor HD4870 1 GB. I agree this card is not optimum for FSX. I took a noticeable frame rate hit going from an nVidia 8800GT to the ATI 4870, but that was with an earlier driver and some of that margin has been clawed back with later driver releases.Cheers,Noel.

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Thanks for your reply Nick! If it's just the video card memory I should keep trying the bufferpools tweak, as the card I have is a PowerColor HD4870 1 GB. I agree this card is not optimum for FSX. I took a noticeable frame rate hit going from an nVidia 8800GT to the ATI 4870, but that was with an earlier driver and some of that margin has been clawed back with later driver releases.Cheers,Noel.
Hi NoelI will be quite frank.. as usual :( LOLATi cards are better suited for shader based rendering engines. They use a different method of AA and they also address the system at the driver level different than Nvidia cards. The facts of life are Nvidia 8800, 260 and 280 series cards are much better suited for MSFS and how it is designed. As such I seriously doubt working bufferpools on that card is going to help you very much. Their drivers address the chipset differently than NvidiaIf MSFS is the application of choice, a single core high end Nvidia should be the card of choice

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Hi NoelI will be quite frank.. as usual :( LOLATi cards are better suited for shader based rendering engines. They use a different method of AA and they also address the system at the driver level different than Nvidia cards. The facts of life are Nvidia 8800, 260 and 280 series cards are much better suited for MSFS and how it is designed. As such I seriously doubt working bufferpools on that card is going to help you very much. Their drivers address the chipset differently than NvidiaIf MSFS is the application of choice, a single core high end Nvidia should be the card of choice
Agreed. I was disappointed with the 4870 from the moment I first fired it up. Now I'm just waiting for the next generation nVidia card before I upgrade.Cheers,Noel.

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Thanks Nick. I just picked up a gtx 285 and cannot wait to try those suggestions.

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Hello Nick, could you expand a little on what fsx.cfg settings I should be using? I am running a 3.0 core2, 4gb ram, vista x64, gtx 285 ocx

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Hello Nick, could you expand a little on what fsx.cfg settings I should be using? I am running a 3.0 core2, 4gb ram, vista x64, gtx 285 ocx
everything you need to know is right here:http://www.simforums.com/forums/forum_posts.asp?TID=29041The only item that does not as of yet cover 'specifically' is bufferpools on a 1GB 280/285 card. The 280/285 1GB Nvidia cards may or may not benefit from a bufferpool setting of between 400000000 and 490000000Bufferpools is not for making large hubs run better, it performs 2 functions: 1. Buffers geometry around the aircraft 2. If set high enough can lower the buss latency smoothing out flight over large amounts of autogen such as large urban and large pine forests with the AG slider set very high or 100%

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Unfortunately that does not solve the 2nd real problem which is the saturation of the reserved bandwidth for the PCIe buss for autogen.. that is where the major bottleneck is and the problem goes back to the design of FSX. FS9 has a max limit of 500 objects per tile. The tiles grew 4x in FSX and instead of the AG limit remaining in line with that they increased it 10+ times the FS9 limit which was not only silly it was a very poor decision based on the hardware at the time.When the Vsync issue was introduced in SP1 whereby stammer in smooth flight is seen it made tuning a smooth experience that much more difficult. Unfortunately the way the app works using the autogen restriction lines in the FSX.cfg file makes for very bad mojo on thread collisions The application posted in this thread actually combats the problem to a certain extent and is probably the best thing to hit the FSX world.. http://forums1.avsim.net/index.php?s=&...t&p=1551461The large memory (1GB) single core 280-285 Nvidia video cards can get smoother perf by increasing bufferpools to 400-490MB not because that amount is needed for FSX but because that will DROP the latency at the driver level on the PCIe buss giving it higher priority to the system for FSX AG. ATi x2 and the 295 Nvidia cards are useless for that tweak (or FSX for that matter) as the 2nd core and memory will not be addressed by FSXWe designed GEX Europe to be in line with hardware standards for autogen and also managed to resolve part of the perf problem around large pine forests in FSX which will effect the sim perf world wide when it is installed.None the less, I don't care how much CPU power the app gets.. FSX is basically a year 2000 triangle rendering engine that will unfortunately never catch up to the shader engine based graphic card designs now in use. In reality the wildly un-optimized design for memory access and thread management gives the user the impression a 5GHz processor will fix all their troubles when the fact of the matter is the application will be just as erratic on 5GHz as it will be on 4, or 3. The difference that is seen as CPU speed increases is not becuse the app needs that CPU power.. its because the lousy way the app address the system it needs that power to visually overcome what I consider the wasted resources and poor memory/cpu access of the design.
Nick, I do have a 285, and one late night I was about falling asleep and thought I read a thread where you talked about providing 500 meg or so to bufferpools. I woke up the next morning and had forgotten all about it until this post. I just went to Vista 64 and am about half way on my OC project for my QX9650, and the OS optimization and some FSX config entries were next on the list to do. Have you any on hands experience, or do you know of someone else where this much bufferpool made a (big) difference? RegardsBob G

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Nick, I do have a 285, and one late night I was about falling asleep and thought I read a thread where you talked about providing 500 meg or so to bufferpools. I woke up the next morning and had forgotten all about it until this post. I just went to Vista 64 and am about half way on my OC project for my QX9650, and the OS optimization and some FSX config entries were next on the list to do. Have you any on hands experience, or do you know of someone else where this much bufferpool made a (big) difference? RegardsBob G
read what I posted above yoursits a try and see setting which both the system in use and drivers can also influenceIt has nothing to do with frame rates and everything to do with smooth over large amounts of autogen, especially tree forests. In the case of the 280/285 cards it can also reduce latency to the buss which has a side effect of curing sound crackle problems with high autogen settings for some usersAlso, to anwer you from another thread, Aniso is harder on a system than trilinear and the very mild visual change it may provide is not worth the hit. LCD and CRT monitors may however display much different results with Aniso enabled and having it enabled on CRT may make enough of a difference to justify the change. There is more to it than just a setting. How well the user has set up FSX correctly and the hardware in play/drivers along with the use of Nhancer makes that call. But the bottom line is Anso does not increase perf. It can increase visual clarity depending on the variables I mentioned. Depending on the scene being rendered it reduces perf. DX10 is of course a different story all together. Users should set to AA enabled and AF to Aniso with DX10

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read what I posted above yoursits a try and see setting which both the system in use and drivers can also influenceIt has nothing to do with frame rates and everything to do with smooth over large amounts of autogen, especially tree forests. In the case of the 280/285 cards it can also reduce latency to the buss which has a side effect of curing sound crackle problems with high autogen settings for some usersAlso, to anwer you from another thread, Aniso is harder on a system than trilinear and the very mild visual change it may provide is not worth the hit. LCD and CRT monitors may however display much different results with Aniso enabled and having it enabled on CRT may make enough of a difference to justify the change. There is more to it than just a setting. How well the user has set up FSX correctly and the hardware in play/drivers along with the use of Nhancer makes that call. But the bottom line is Anso does not increase perf. It can increase visual clarity depending on the variables I mentioned. Depending on the scene being rendered it reduces perf. DX10 is of course a different story all together. Users should set to AA enabled and AF to Aniso with DX10
Ok. Understood. I am testing my system at an airport used in FTX. Wow what nice stuff, but extremely hard on a system. And yes, I do have an LCD, so this is why I see the cleaner scenery. What is interesting is that there is no difference in smoothness between the two. Ansio, is very smooth on my system. You are one busy guy!!!! Your input is valuable to me and countless others in the community, and I thank you for your contributions, time and energy.RegardsBob G

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