I didn't have a previous system, this is one I build for other person. The location I flew was the location of redbull air race mission in FSX, not something like JFK and with default scenery generation, nothing special. Yes indeed the processor will be >92% with affinity set to 254, if set to 255 and priority higher for TrackIR, it slows actually. Do you have reference to where it is said that SP1 disabled hyperthreading? I fly SP2, I do not understand how an application can tell the difference between a processor and a hyperthreaded portion of a processor? It seems like the OS makes that transparent and presents it as 8 cores. Thanks.

Here: http://blogs.msdn.com/ptaylor/archive/2007...ntel-quote.aspxQuote: "Note - hyperthreaded is not multi-core. Our current plan is to treat HT machines as single-core since we noticed extensive collisions between threads which caused stutters."Perhaps i7 hyperthreading is different. I guess there's some way to mark your application as "not for HT" when it is compiled, and the Windows scheduler can recognise that? All pure speculation on my part as I rarely work in C.RegardsSimon

I thought AffinityMask was removed with SP2/Accel? ??

I believe he is referencing the old P4 HT, which was failure, Nehalem is completely different from what I understand from conventional HT.

I believe he is referencing the old P4 HT, which was failure, Nehalem is completely different from what I understand from conventional HT.

I read further in the blog about FSX "ignoring" logical cores as presented by the operating system. If HT shows up as physical cores and the thread collisions seen with earlier processors is not occuring, then we have a very good thing here! HT won't double processing over a single core, but it will help.

I read further in the blog about FSX "ignoring" logical cores as presented by the operating system. If HT shows up as physical cores and the thread collisions seen with earlier processors is not occuring, then we have a very good thing here! HT won't double processing over a single core, but it will help.

There are differences between Nehalem's SMT implementation and its Netburst predecessors. What those are I don't yet know, but I'm looking into it. I'll post back when I have the answer.

There are differences between Nehalem's SMT implementation and its Netburst predecessors. What those are I don't yet know, but I'm looking into it. I'll post back when I have the answer.

After some further searching there does not appear to be any difference in the implementation of SMT in Nehalem compared to Netburst family processors. The differences are architectural and they are simply an enlarged Re-Order Buffer and additional Reservation Stations. These changes allow Nehalem to maintain performance across multiple threads when SMT is enabled. Previous Netburst family processors could experience a significant performance decrease with SMT enabled in scenarios with only a single heavyweight thread running.

I have made some obsevations when running FSX on an i7 CPU. My old rig was an E8600 overclocked to 4.33Ghz. My new rig is an i7 965, initially at 3.2Ghz but now overclocked to 4Ghz. I used the same OS, Vista 64 and graphics card, a 280 GTX. I mostly fly over the UK using photo scenery with addon airports/scenery such as Aerosoft Heathrow, VFR London and UK2000 airports. The ai I use is My Traffic X. I normally keep scenery complexity to dense and autogen to medium for when I'm flying outside the UK. With the E8600 at 4.33Ghz and the i7 at 3.2 Ghz, the average FPS were slightly higher on the E8600. These are just numbers however and when actually flying, the i7 was far smoother and fluid, more akin to X-Plane's smoothness. It gave the impression that the FPS were higher. When flying over photo scenery, all 4 cores are being heavily utilized however when flying over default scenery, 3 cores aren't being used much at all except when approaching a city or major airport. I put the smoothness of the i7 down to the fact it has more cores than the E8600 and a much faster memory interface so it can load and process data more quickly.I like to fly with the FPS at least 20, preferably more, however when flying into very dense scenery areas such as KJFK in PMDG 747, the FPS still dropped to the mid to low teens which I notice and it spoils the illusion of flight a bit for me. I decided to overclock the i7 and managed to acheive 4Ghz with voltages and temperatures well within Intel Specs, suilable for 24/7 use. As a test for my own information, I used Fraps to measure average FPS on a flight from EGLC (London City) to EGLL (Heathrow), over Aerosoft London with photo scenery installed in the Flight 1 ATR 72. The E8600 @ 4.33Ghz and i7 @ 3.2Ghz both managed around 15 FPS average however the min FPS for the E8600 was 2 as opposed to 8 for the i7. Both maxed out at 27 FPS. The i7 overclocked to 4Ghz managed an average 18 FPS with a min 10 and again, a max of 27 FPS. Switching Hyperthreading on and off in the Bios didn't make any difference to performance except that Task Manager shows up with 8 cores. These are really worst case scenarios, flying over really dense areas with a complex addon aircraft with ai traffic at 40 % etc. Normally, with my settings in default scenery areas, the FPS stays well above 30 with either CPU. I think that the i7 is definately a faster CPU for FSX, certainly making for much smoother flights however it's not a massive improvement even when overclocked and I still found myself tweaking the FSX.CFG file. FSX is definately CPU bound, running the actual flying part on one core and scenery loading on the remainder. I don't think a CPU will be released in the lifespan of FSX which will allow all the sliders set to maximum over complex scenery areas. For this, you would need a CPU clocked to at least 8Ghz regardless of the architecture.

I have made some obsevations when running FSX on an i7 CPU. My old rig was an E8600 overclocked to 4.33Ghz. My new rig is an i7 965, initially at 3.2Ghz but now overclocked to 4Ghz. I used the same OS, Vista 64 and graphics card, a 280 GTX. I mostly fly over the UK using photo scenery with addon airports/scenery such as Aerosoft Heathrow, VFR London and UK2000 airports. The ai I use is My Traffic X. I normally keep scenery complexity to dense and autogen to medium for when I'm flying outside the UK. With the E8600 at 4.33Ghz and the i7 at 3.2 Ghz, the average FPS were slightly higher on the E8600. These are just numbers however and when actually flying, the i7 was far smoother and fluid, more akin to X-Plane's smoothness. It gave the impression that the FPS were higher. When flying over photo scenery, all 4 cores are being heavily utilized however when flying over default scenery, 3 cores aren't being used much at all except when approaching a city or major airport. I put the smoothness of the i7 down to the fact it has more cores than the E8600 and a much faster memory interface so it can load and process data more quickly.I like to fly with the FPS at least 20, preferably more, however when flying into very dense scenery areas such as KJFK in PMDG 747, the FPS still dropped to the mid to low teens which I notice and it spoils the illusion of flight a bit for me. I decided to overclock the i7 and managed to acheive 4Ghz with voltages and temperatures well within Intel Specs, suilable for 24/7 use. As a test for my own information, I used Fraps to measure average FPS on a flight from EGLC (London City) to EGLL (Heathrow), over Aerosoft London with photo scenery installed in the Flight 1 ATR 72. The E8600 @ 4.33Ghz and i7 @ 3.2Ghz both managed around 15 FPS average however the min FPS for the E8600 was 2 as opposed to 8 for the i7. Both maxed out at 27 FPS. The i7 overclocked to 4Ghz managed an average 18 FPS with a min 10 and again, a max of 27 FPS. Switching Hyperthreading on and off in the Bios didn't make any difference to performance except that Task Manager shows up with 8 cores. These are really worst case scenarios, flying over really dense areas with a complex addon aircraft with ai traffic at 40 % etc. Normally, with my settings in default scenery areas, the FPS stays well above 30 with either CPU. I think that the i7 is definately a faster CPU for FSX, certainly making for much smoother flights however it's not a massive improvement even when overclocked and I still found myself tweaking the FSX.CFG file. FSX is definately CPU bound, running the actual flying part on one core and scenery loading on the remainder. I don't think a CPU will be released in the lifespan of FSX which will allow all the sliders set to maximum over complex scenery areas. For this, you would need a CPU clocked to at least 8Ghz regardless of the architecture.

Terry - Thanks for this: this is exactly the sort of comparison I've been hoping to see. I think the critical factor is how much better the minimum FPS become, because this is the number which best indicates the sense of smoothness or stutter one is likely to experience. Your numbers suggest that there is a signficicant improvement.Tim

I have made some obsevations when running FSX on an i7 CPU. My old rig was an E8600 overclocked to 4.33Ghz. My new rig is an i7 965, initially at 3.2Ghz but now overclocked to 4Ghz. I used the same OS, Vista 64 and graphics card, a 280 GTX. I mostly fly over the UK using photo scenery with addon airports/scenery such as Aerosoft Heathrow, VFR London and UK2000 airports. The ai I use is My Traffic X. I normally keep scenery complexity to dense and autogen to medium for when I'm flying outside the UK. With the E8600 at 4.33Ghz and the i7 at 3.2 Ghz, the average FPS were slightly higher on the E8600. These are just numbers however and when actually flying, the i7 was far smoother and fluid, more akin to X-Plane's smoothness. It gave the impression that the FPS were higher. When flying over photo scenery, all 4 cores are being heavily utilized however when flying over default scenery, 3 cores aren't being used much at all except when approaching a city or major airport. I put the smoothness of the i7 down to the fact it has more cores than the E8600 and a much faster memory interface so it can load and process data more quickly.I like to fly with the FPS at least 20, preferably more, however when flying into very dense scenery areas such as KJFK in PMDG 747, the FPS still dropped to the mid to low teens which I notice and it spoils the illusion of flight a bit for me. I decided to overclock the i7 and managed to acheive 4Ghz with voltages and temperatures well within Intel Specs, suilable for 24/7 use. As a test for my own information, I used Fraps to measure average FPS on a flight from EGLC (London City) to EGLL (Heathrow), over Aerosoft London with photo scenery installed in the Flight 1 ATR 72. The E8600 @ 4.33Ghz and i7 @ 3.2Ghz both managed around 15 FPS average however the min FPS for the E8600 was 2 as opposed to 8 for the i7. Both maxed out at 27 FPS. The i7 overclocked to 4Ghz managed an average 18 FPS with a min 10 and again, a max of 27 FPS. Switching Hyperthreading on and off in the Bios didn't make any difference to performance except that Task Manager shows up with 8 cores. These are really worst case scenarios, flying over really dense areas with a complex addon aircraft with ai traffic at 40 % etc. Normally, with my settings in default scenery areas, the FPS stays well above 30 with either CPU. I think that the i7 is definately a faster CPU for FSX, certainly making for much smoother flights however it's not a massive improvement even when overclocked and I still found myself tweaking the FSX.CFG file. FSX is definately CPU bound, running the actual flying part on one core and scenery loading on the remainder. I don't think a CPU will be released in the lifespan of FSX which will allow all the sliders set to maximum over complex scenery areas. For this, you would need a CPU clocked to at least 8Ghz regardless of the architecture.

Thanks Terry it is indeed very instersting your results Im glade you used airports like egll and the pmdg aircraft. I know the default of course will get a higher fps depeding on what area but my insterst are in big airports and citys.

I have made some obsevations when running FSX on an i7 CPU. My old rig was an E8600 overclocked to 4.33Ghz. My new rig is an i7 965, initially at 3.2Ghz but now overclocked to 4Ghz. I used the same OS, Vista 64 and graphics card, a 280 GTX. I mostly fly over the UK using photo scenery with addon airports/scenery such as Aerosoft Heathrow, VFR London and UK2000 airports. The ai I use is My Traffic X. I normally keep scenery complexity to dense and autogen to medium for when I'm flying outside the UK. With the E8600 at 4.33Ghz and the i7 at 3.2 Ghz, the average FPS were slightly higher on the E8600. These are just numbers however and when actually flying, the i7 was far smoother and fluid, more akin to X-Plane's smoothness. It gave the impression that the FPS were higher. When flying over photo scenery, all 4 cores are being heavily utilized however when flying over default scenery, 3 cores aren't being used much at all except when approaching a city or major airport. I put the smoothness of the i7 down to the fact it has more cores than the E8600 and a much faster memory interface so it can load and process data more quickly.I like to fly with the FPS at least 20, preferably more, however when flying into very dense scenery areas such as KJFK in PMDG 747, the FPS still dropped to the mid to low teens which I notice and it spoils the illusion of flight a bit for me. I decided to overclock the i7 and managed to acheive 4Ghz with voltages and temperatures well within Intel Specs, suilable for 24/7 use. As a test for my own information, I used Fraps to measure average FPS on a flight from EGLC (London City) to EGLL (Heathrow), over Aerosoft London with photo scenery installed in the Flight 1 ATR 72. The E8600 @ 4.33Ghz and i7 @ 3.2Ghz both managed around 15 FPS average however the min FPS for the E8600 was 2 as opposed to 8 for the i7. Both maxed out at 27 FPS. The i7 overclocked to 4Ghz managed an average 18 FPS with a min 10 and again, a max of 27 FPS. Switching Hyperthreading on and off in the Bios didn't make any difference to performance except that Task Manager shows up with 8 cores. These are really worst case scenarios, flying over really dense areas with a complex addon aircraft with ai traffic at 40 % etc. Normally, with my settings in default scenery areas, the FPS stays well above 30 with either CPU. I think that the i7 is definately a faster CPU for FSX, certainly making for much smoother flights however it's not a massive improvement even when overclocked and I still found myself tweaking the FSX.CFG file. FSX is definately CPU bound, running the actual flying part on one core and scenery loading on the remainder. I don't think a CPU will be released in the lifespan of FSX which will allow all the sliders set to maximum over complex scenery areas. For this, you would need a CPU clocked to at least 8Ghz regardless of the architecture.

Thanks for the report

Thanks for the detailed comparison, Terry. I'm in the process of building a rig identical to yours... CPU, video card, Vista 64. I'm using an Asus P6T mobo. Would you mind revealing the multiplier and voltages you ended up with to get the 4 GHz. and the pertinent .CFG changes? I believe NickN posted multiplier and voltages for 4 GHz. also, and it would be helpful to compare yours and his.Thanks,Jeff

Thanks for the detailed comparison, Terry. I'm in the process of building a rig identical to yours... CPU, video card, Vista 64. I'm using an Asus P6T mobo. Would you mind revealing the multiplier and voltages you ended up with to get the 4 GHz. and the pertinent .CFG changes? I believe NickN posted multiplier and voltages for 4 GHz. also, and it would be helpful to compare yours and his.Thanks,Jeff

Hi Jeff, I am also using a P6T Delux. The only thing I done was within the Bios, go to Ai Tweaker and set Ai Overclock Tuner to manual. Remaining within Ai Tweaker, I set the CPU Ratio to 30 and set the CPU Voltage to 1.3v. I also manually set the Dram Bus Voltage to 1.64v and left everything else on auto. I'm using 1600 Mhz Ram so I made sure that it was set properly as it defaults to 1333 Mhz. I am using a Thermalright Ultra CPU Cooler within an Antec 1200 case to ensure cooling is OK. I ran Prime95 overnight, about 8 hours and recorded temperatures with CoreTemp. The maximum temperature reached was around 63C. As I'm writing this it's idling at 34C and when running FSX it goes up to around 57C. I found that if you leave the CPU Voltage on auto, it puts it far higher than is needed, over 1.4v for 3.733 Ghz which is why I also manually set the Dram Bus Voltage to 1.64v, just in case.

Thanks, Terry. I'm running Thermalright cooler (if I can ever get one, maybe another week) and 1600 RAM here, too with a CoolerMaster CM 690 case. It's good to know the values to get in the ballpark safely. I've never OCed before so I don't want to blow out an expensive processor first time out of the chute. I believe Nick achieved the same 4GHz. with a little higher voltage and a little lower multiplier. I guess there's more than one way to skin a cat. Nick, if you're reading this, is there an advantage to running the lower mulitplier and higher voltage or is it 6 of one and a half dozen of the other? Thanks,Jeff

Always go for the lower voltage option as higher voltages reduce processor lifetime.

Hi to you all,and thanks Terry, for the performance report.Regarding all FPS numbers which are reported, I have two questions (I don't think that this is mentioned, sorry, if I didn't see it):1. do you use anti aliasing (4x? 8x?) and do you use it via FSX graphics settings or via the gfx driver?2. what's your resolution?Thanks,Roger