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Guest TU0833

Picking The Right Cpu For Fsx

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i plan to upgrade soon to FSX but before i need to upgrade both my CPU and GPUfor the CPU i'm hesitating between the Q9550 LINKand the Core Duo E8600 LINKfrom what i read, FSX uses 2 cores so the quad might be a waste of power. is that true?which one will give the highest frame rates if combined with a GTX 260? do i need to purchase a new motherboard with the CPU? mine is from Dellnote: i won't overclock the heater in my house works fine :(

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If you are not planning to overclock the Dual core then the Q9550 quad is by far the better bet for FSX. FSX will use all 4 cores (it will use 256 of them if you had that many) and you will see smoother overall performance with the Quad Core. Same applies for the combination of GTX260 - go with the Q9550. Quad Cores are a much better investment for the future anyway.Not possible to say whether you will need a new motherboard without knowing exactly which model you have. The Q9550 is the newer 45nm CPU and some older motherboards will not be compatible. The Q9550 (and E8600) runs on a 1333FSB so having a mobo that can match that will bring measureable benefits. The GTX260 will also benefit from a PCIE 2.0 slot, something your current mobo may not have. If Dell offers the Q9550 and the GTX260 as an upgrade option for your machine then you will be fine. I would check with Dell direct anyway to be sure.Edit: forgot to mention that you will most probably have to look at whether your current Power Supply Unit (PSU) can handle your new GTX260, both from a wattage point of view and from a connector point of view. If you have a fairly recent PSU rated at around 450W to 550W you should be ok. If not then you will have to get a new PSU. Power PC & Cooling, Corsair and a few other PSU brands are well worth picking up.Hope this helps!

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Thanks Sharrow. That helps alot! I'll check my machine carefully especially the motherboard and the PSU. I hate wasting money!

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I think you have it backwards.If he's not going to OC at all, he'll want the E8600 because of the faster clock speed. The clock speed will give higher FPS and ability to fly in more dense areas. If you only fly in rural areas then sure, get the Q

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I think you have it backwards.If he's not going to OC at all, he'll want the E8600 because of the faster clock speed. The clock speed will give higher FPS and ability to fly in more dense areas. If you only fly in rural areas then sure, get the Q
Nope, I do not believe I have it backwards. 2.83GHz stock on the Q9550 vs 3.3GHz stock on the E8600 is not, in my opinion, difference enough to make up for the loss of 2 very useable cores. A difference of 800MHz+ and we're getting somewhere. Throw in some addon scenery or some heavy weather, a bit of AI or a complex heavy and the E8600 is going to start maxing those 2 cores very, very quickly.Hitting the highest FPS possible is one thing - having a consistently useable minimum FPS (on finals in particular) is quiet another.Just my opinion of course.

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Nope, I do not believe I have it backwards. 2.83GHz stock on the Q9550 vs 3.3GHz stock on the E8600 is not, in my opinion, difference enough to make up for the loss of 2 very useable cores. A difference of 800MHz+ and we're getting somewhere. Throw in some addon scenery or some heavy weather, a bit of AI or a complex heavy and the E8600 is going to start maxing those 2 cores very, very quickly.Hitting the highest FPS possible is one thing - having a consistently useable minimum FPS (on finals in particular) is quiet another.Just my opinion of course.
All those extra cores are going to do is load textures. Pre-fetching textures can minimize brief pauses, but will not affect FPS other than when displaying new textures. FSX is not so well multi-threaded that it will truly stress > 2 cores. The extra core clock of the E8600 will in fact deliver higher FPS. The Q will be a "no-brainer" (no additional tweaking necessary to get optimal performance) whereas the E will take a bit of additional tweaking to avoid these pauses. That being said, both are fine processors and I doubt the OP will regret choosing either.

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FSX is not so well multi-threaded that it will truly stress > 2 cores.
This may well be the stupidest question posted here today but is FSX multi-threaded at all? I was under the impression that it is the OS which is in fact responsible for "directing the workload" as it were across multiple cores?EDIT: Please ignore the question. My misunderstanding between multi-threaded and multi-process!EDIT 2: SimHQ seems to have an interesting take on this. http://simhq.com/forum/ubbthreads.php/topics/2605143/1.html

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This may well be the stupidest question posted here today but is FSX multi-threaded at all? I was under the impression that it is the OS which is in fact responsible for "directing the workload" as it were across multiple cores?EDIT: Please ignore the question. My misunderstanding between multi-threaded and multi-process!EDIT 2: SimHQ seems to have an interesting take on this. http://simhq.com/forum/ubbthreads.php/topics/2605143/1.html
The following is in no way a disagreement or rebuke, it is simply a clarification to avoid potential confusion:The key is in the details. Note that I'm not saying "FSX isn't multi-threaded", just that it doesn't execute enough heavyweight threads to stress more than 2 cores. Loading textures via new threads does not make heavyweight work. It has a purpose, it just doesn't contribute to performance outside of specific scenarios (when loading and displaying new textures).

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The following is in no way a disagreement or rebuke, it is simply a clarification to avoid potential confusion:The key is in the details. Note that I'm not saying "FSX isn't multi-threaded", just that it doesn't execute enough heavyweight threads to stress more than 2 cores. Loading textures via new threads does not make heavyweight work. It has a purpose, it just doesn't contribute to performance outside of specific scenarios (when loading and displaying new textures).
Please correct me if I am wrong but is this "specific scenario" of loading and displaying new textures not something that happens pretty often with FSX? The suggestion seems to be that this is an isolated event here and there but considering all that happens when on finals into a big airport logic would have it that loading and displaying new textures (not to to mention autogen and what not else) is in fact a big part of what is going on. At FL320 things are a bit different, but then no one really complains about FPS at altitude...My understanding is that more than just texture loading happens on cores 3 & 4, my mention of autogen is on purpose.

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Please correct me if I am wrong but is this "specific scenario" of loading and displaying new textures not something that happens pretty often with FSX? The suggestion seems to be that this is an isolated event here and there but considering all that happens when on finals into a big airport logic would have it that loading and displaying new textures (not to to mention autogen and what not else) is in fact a big part of what is going on. At FL320 things are a bit different, but then no one really complains about FPS at altitude...My understanding is that more than just texture loading happens on cores 3 & 4, my mention of autogen is on purpose.
It happens most when transitioning to new areas. I imagine if one were flying high enough and fast enough this could always occur, but I would hope Aces is smart enough to use a Level of Detail texturing system and not just load in the same quality of textures regardless of camera position and altitude.But you seem to be missing the forest for the trees, here.My point is that loading anything is not a processing intensive task, and thus disqualifies these threads from being classified as heavyweight threads, which means they don't stress the processor cores upon which they run.

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Sharrow,Ryan and Techguy are both correct. The extra cores on the Quad are only used for texture loading. The end result being elimination or reduction in the "blurries". The orginal poster of this thread will be much better off going for the faster clocked dual core if he/she is not going to overclock.The system I had prior to my present system was an E6850 OC'd to 3.8Ghz and FPS wise in FSX was pretty much identical to my present system QX9650 OC'd to 3.8Ghz. The major difference between then and now is that I have no blurries at all with the quad core and FSX overall is much smoother. The bottm line is that the additional 500Mhz of the dual core will go a long way to improving the overall performance of FSX especially when the brunt of the work is done on the first two cores. Utilization of the lower clocked Quad would result in much decreased performance within FSX.

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Sharrow,Ryan and Techguy are both correct. The extra cores on the Quad are only used for texture loading. The end result being elimination or reduction in the "blurries". The orginal poster of this thread will be much better off going for the faster clocked dual core if he/she is not going to overclock.The system I had prior to my present system was an E6850 OC'd to 3.8Ghz and FPS wise in FSX was pretty much identical to my present system QX9650 OC'd to 3.8Ghz. The major difference between then and now is that I have no blurries at all with the quad core and FSX overall is much smoother. The bottm line is that the additional 500Mhz of the dual core will go a long way to improving the overall performance of FSX especially when the brunt of the work is done on the first two cores. Utilization of the lower clocked Quad would result in much decreased performance within FSX.
A Quad will offload autogen, terrain geometry and textures and I do believe Phil Taylor mentioned in one of our discussions AI may also benefit but I do not remember exactly what part of AI may be offloaded to other cores. Rule of thumb, if CPU is 500MHz+ faster a dual may be better under most scenery conditions, less or equal quad will always be betterand I would always go with the quad if I had to chose between 4 and 4.5GHzThe Q9650 E0 stepping proc is what I would use, run it at 450MHz on the 333 STRAP at DDR2 1081 5-5-5 2.1v and 1.25-1.28 FSB Termination voltage and between 1.28 and 1.33vcore. Requires the right CPU cooler.. OCZ Vendetta2 or Thermalright 120The 9550 is a 8.5 multiplier with 2 possible stepping version available.. if not E0 it wont hit the higher speeds where the 9650 is a E0 chip and will do 4050GHzIf the choice is between a 3.6/3.8GHz quad and a 4.2-4.5GHZ dual then the dual would be a better choiceThe advantage to DDR3 systems is they have the ability to run those CPUs at high memory speed and higher FSB.The choice of the CPU in DDR2 is limited to about 450MHz @ multiplier on the right memory, or, a high multiplier CPU on 400MHz FSB, or, an extreme processor that has high clock ability and of course any multiplier needed to get there @ FSB

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The advantage to DDR3 systems is they have the ability to run those CPUs at high memory speed and higher FSB.The choice of the CPU in DDR2 is limited to about 450MHz @ multiplier on the right memory, or, a high multiplier CPU on 400MHz FSB, or, an extreme processor that has high clock ability and of course any multiplier needed to get there @ FSB
Memory speeds are of course higher on DDR3 platforms, but the FSB clock is independent of memory clock, which is why memory ratios exist. I run 1:1 on my system at 2GHz/1GHz FSB/RAM speeds (500MHz quad-pumped FSB = "2GHz", DDR 500MHz = "1GHz" in marketing speak). I don't see many DDR3 systems out there with higher than 2GHz FSBs.

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Thanks for all the clarifications gentlemen!Going by what Nick said about the dual core needing to be at least 500Mhz faster it stands to reason that the OP, who was not going to oc, would indeed be better off with the Q9550 as opposed to the E8600."A Quad will offload autogen, terrain geometry and textures and I do believe Phil Taylor mentioned in one of our discussions AI may also benefit but I do not remember exactly what part of AI may be offloaded to other cores." That's a fair chunk of work being offloaded to cores 3 & 4. More so than most folks realise I reckon...I can begin to see why the FSX quad vs dual core debate has been called a dead horse. Seems to be pretty difficult, if not impossible, to reach a satisfactory conclusion about this issue and I suspect that most folk starting such threads end up walking away more confused than before. Also worth a mention is the fact that FSX is rarely the only application a user would run on their rigs and when it comes to general multi-tasking and playing new AAA titles quads are beginning to take over en-force. Far Cry 2 is a good example of this. For those who upgrade at every opportunity this may not matter but for the majority of folks this consideration is an important one.

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My point is that loading anything is not a processing intensive task, and thus disqualifies these threads from being classified as heavyweight threads, which means they don't stress the processor cores upon which they run.
By stressing the core we are talking 95%+ utilization, more or less?I am not saying or implying that loading textures (and all the rest Nick mentioned) is going to stress any given core, what I am saying is that all this offloading to core 3 & 4 simply provides core 1 & 2 with more available cycles to get on with the really important bits. Hence the "rule of thumb" 500MHz+ extra you need on a dual core to make up for the loss of 2 cores...I have read on many, many occasions of high end FSX users stressing their dual cores on a regular basis and then moving to quad and experiencing significantly lower CPU utlization across their 4 cores. This speaks for itself, does it not? Am I still missing the forest for the trees here?

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Not to mention that with a quad one also has the possibility of setting affinity to specific cores (core 4 for example) for addons which run alongside FSX, thereby keeping the addon well away from the business end of things as it were. If you run windowed mode on multi-monitor set ups you can achieve the same effect with other apps you may be running alongside FSX. All sweet goodness, no?Sorry, will shut up now and let you all wake up over there and have a chance to respond... :(

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By stressing the core we are talking 95%+ utilization, more or less?
Depends on the application. Most "stress-tests" run the CPU as close to 100% as possible so I'd say that's really stressing the core. Most applications are designed to take as many clock cycles as they can, if they are computationally-heavy. In this case though it appears FSX is basically just constantly issuing memory requests on the extra cores, so while they are kept busy, they're not contributing significantly to performance because they're not performing any computational work.
I am not saying or implying that loading textures (and all the rest Nick mentioned) is going to stress any given core, what I am saying is that all this offloading to core 3 & 4 simply provides core 1 & 2 with more available cycles to get on with the really important bits. Hence the "rule of thumb" 500MHz+ extra you need on a dual core to make up for the loss of 2 cores...
It's true that offloading work to spare cores helps free up cycles on the busier cores, hence the extra clockspeed (i.e. extra cycles) needed to make up for this fact.
I have read on many, many occasions of high end FSX users stressing their dual cores on a regular basis and then moving to quad and experiencing significantly lower CPU utlization across their 4 cores. This speaks for itself, does it not? Am I still missing the forest for the trees here?
Well if you double the number of cores and run the same workload, of course your CPU utilization will decrease as a percent. This doesn't imply any increase in performance though. In fact, an increase in performance would likely be noted under similar utilization numbers after doubling the cores as this would mean 2 cores was not enough to handle the workload in the same time as 4 cores. Bottom-line: the extra cores are useful, but not for computational work, meaning they will not significantly increase frame rates (again, except during load times).
Not to mention that with a quad one also has the possibility of setting affinity to specific cores (core 4 for example) for addons which run alongside FSX, thereby keeping the addon well away from the business end of things as it were. If you run windowed mode on multi-monitor set ups you can achieve the same effect with other apps you may be running alongside FSX. All sweet goodness, no?Sorry, will shut up now and let you all wake up over there and have a chance to respond... :(
That's the point though - you have to find extra work for your extra cores, FSX won't do it for you automatically.

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frame rates after a smooth 24-30 is not a concern for me. Scenery, clarity and smooth perf, is

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frame rates after a smooth 24-30 is not a concern for me. Scenery, clarity and smooth perf, is
Certainly. Still have to get there though. 24-30 fps is easier said than done particularly in urban environments with heavy traffic and autogen.In other words: there is a use for "extra" CPU horsepower which delivers "extra" frames, and that is in scenarios where those "extra" frames disappear, such as that I just described.

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Certainly. Still have to get there though. 24-30 fps is easier said than done particularly in urban environments with heavy traffic and autogen.In other words: there is a use for "extra" CPU horsepower which delivers "extra" frames, and that is in scenarios where those "extra" frames disappear, such as that I just described.
I dont seem to have that FPS drop problem hereFrames can not be used to judge perf on any linear scale,... that approach don't work with FSXtoo many variables in play in free flightOne can use frame rates as 'part' of an indicator if, and only if, the flight is 100% controlled with a flight file which can be repeated and a compare can be gauged against a hardware change/driver change/settings changehowever the FR is only part of the result in that quantified examinationotherwise FR are just about out of the loop for use in proper examination of a result in FSX

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Sure but a E8600 will get you there faster than a quad will...Say FPS don't matter, ok, but there will be a level at which the user sets autogen/scenery/etc options at. I guess it comes down to, would you rather have a low framerate (15-20 FPS) in large cities but no stutters, or 24-30FPS in the same area with a few microstutters? I'd take the 24-30, especially once you add in payware planes like the PMDG/Level D stuff. And btw, 3.33ghz -2.83 ghz = 500 Mhz

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I dont seem to have that FPS drop problem hereFrames can not be used to judge perf on any linear scale,... that approach don't work with FSXtoo many variables in play in free flightOne can use frame rates as 'part' of an indicator if, and only if, the flight is 100% controlled with a flight file which can be repeated and a compare can be gauged against a hardware change/driver change/settings changehowever the FR is only part of the result in that quantified examinationotherwise FR are just about out of the loop for use in proper examination of a result in FSX
MSFS' FPS counter isn't real-time. Your entire argument ignores this crucial fact. The cause for these frames not being displayed is irrelevant, the result is a lack of perceived motion because frames aren't being rendered.

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