FSX is CPU Constrained

[Guest concern]

After a week of patient tweaking, I've come to the conclusion that FSX appears to be mostly CPU constrained.My system config is P4 3GHz, 2GB RAM and an XT850 AGP video card, so it's not the most highly specified system. I have, however, been able to get the game to run at quite acceptable (ie: playable) frame rates; 15+ most of the time with occasional dips below 10.Here are some of my observations that have led me to this conclusion. I would be keen to hear from others to support and/or refute these observations!* A lot of the graphical detail settings have negligible impact on my frame rates.* anisotropic filtering and antialiasing have no noticeable impact when enabled* water textures L/M shader 2 settings provide great effects and only a small frame rate hit* and here's the clincher...changing resolution from 1280x800 (I have a 16:10 monitor) to 1920x1200 - no frame rate impact! While it seems unbelievable it is quite probable in a CPU bound application. And running FSX at this resolution provides beautiful detail in both the scenery and cockpits.* and another one that points to CPU bound issues - AI traffic, ground, sea and air seem to have the most significant framerate impact. I am running on minimal settings at the moment :-( and have a consistent framerate. When I start bumping up the values, the frame rate starts to fluctuate wildly - just sitting there on the runway with a static view, the framerates just keep jumping about. Obviously AI traffic takes significant cycles from the CPU which is busy rendering the view.Overall, I am pretty happy with FSX. The scenery is wonderful, the 3D cockpits are excellent and the overall experience is pretty good.What frustrates me the most is not being able to understand the clear relationship between the display settings and the gaming experience. Changing a setting always seems to have unpredictable results, and this is annoying. It would be nice to a) understand the performance impact of every setting and :( understand the difference in gaming experience (image quality) of every setting.Graham

[Guest concern]

I forgot to add that the G1000 is also CPU intensive. It's a great way to ensure that my framerates plummet, which is a pity.

[GHarrall 494]

Hi Graham,No disrespect, but every version has been CPU constrained and has been known about for years. Nothing has changed with FSX.......

[Guest BOPrey]

"I reduced the gpu core speed by 1/3, no change in FR. (Tests shader app speed)I reduced memory speed in the graphics card, no change in FR. (Tests texture rasterizing speed)I set AGP from 8X to 4X, no change in FR.I increased system memory latance by a third, no change in FR.I reduced CPU clock speed by 1/3, FR dropped by 1/3.This looks to me FSX is very CPU limited. If I want to get 20 fps over that same area, I might have to get a 6.4GHz cpu. Wish me luck. However, I am OK with 15 fps. So, at the moment, I am building a c2d and will overclocked to 3.5GHz or above which will deliever 5.25GHz of raw P4 speed. "http://forums.avsim.net/dcboard.php?az=sho..._id=20047&page=

[Guest Ozzie]

I think that you could quite possible spend the next six monts tweaking to knobble various features and still come to the same conclusionIt is a strange coincidence that one of the ACES team that appeared to be too candid has moved on to other things (as an ex-employee - I wish him luck)You may also wish to use Google and make up your own mind about the relationship with Vista - you may wish to convey your thoughts to the comany concerned

[Guest concern]

Thanks. I am only a casual flight simmer, so I didn't stop to think about this. So the good news is that with this in mind, it's only a matter of qualifying whether each of the display options either requires substantial CPU cycles or can be offloaded to the graphics card. Most of the latter can then be enabled!

[yellowjack 28]

So you have finally come to believe that the world is round and has been that way since Adam was a boy.Welcome to the club. ;)

[PhilTaylor 45]

Obvious troll and completely answered in other threads.TDragger has not had anything bad happen to him, he is still here in Aces just on a new project. Given FSX has shipped, thats a completely natural evolution.Stop this conspiracy theory junk, its just not true.Phil

[Guest dnunez_za]

Not understanding the link between display settings and performance is not just your frustration - it is a nightmare for designers also.There are a number of other factors in a simulation which affect the update rate:1. RAM bus speed - how fast you push data between memory, the CPU and the graphics bus into graphics RAM2. secondary storage transfer rates - how quickly you can ship data between the hard disks and RAM; FSX (and FS9 and FS8) spool scenery etc from the drive constantly, so this can be an issue3. the bandwidth between the CPU and the sound card, and the efficeincy of the sound card D-to-A convertersAnd then these things all interact in strnage ways; for instance, if your cpu is really fast, but your hard drive and RAM can't feed it data fast enough, you don't get advantage. Of if you have a very fast cpu with lots of bandwidth to the ram, but your hard drive is fragmented, you are not feeding data fast enough to those; and so on (and then the nightmare of thread and fibre scheduling, which can lead to cpu pipeline stalls, and a lot of other things). The CPU takes the biggest load because essentially the heart of FSX is a lot of physics equations (flight model, weather model, plus the AI of the traffic, cars and boats), with a scenery engine around that, and then a gfx and sound display system around all that. The graphics card (and most display settings) only affect that outer layer. Games like Oblivion (to take an example of a recent non-sim) have very little (in relative terms) in simulation (just AI and driving the story, which is quite cheap), so they get away with having great frame rates, and they benefit massively from upgrades to the graphics card.I must say, having some know-how about how simulation works, I am absolutely bowled over by FSX performance. I did upgrade my machine to run it (it was due for an upgrade anyway), and yes it can be set to run more slowly than FS9 if you turn things up, but I have spent a good while tweaking and experimenting based on various forum posts and other sources, and for about the same frame rates as FS9, it looks better, and gives a better experience of flight than fs9. The best part for me is, unlike FS9, in three years time, it will be running absolutely great, and run fantastic; and the new features (like simconnect) are going to mean a huge slew of new add-ons which FS9 could not hope for.

[Guest haklis]

>* A lot of the graphical detail settings have negligible>impact on my frame rates.>GrahamThat was the case with me too. Always got 5-15fps no matter what I did of tweaks and settings - until yesterday. I updated my BIOS and WOW! I did not believe my eyes! fps from 30-70! (With low sliders), and after adding more graphic complexity I flew with 20-30 fps at Friday Harbour. In Seattle it dropped back to 5-15fps on max settings though. :-)Hakon

[Guest Jimbofly]

The jury's still out until DX10 cards are released.James

[Guest Alan van der Vyver]

> The jury's still out until DX10 cards are released.That may be, but if the previous posts are correct, it does not appear that improved graphics systems are going to help very much.It also means that the future performance prospects are quite bleak for this release. Upgrading hardware may not be a good proposition, because the trend is definitely to slower CPU's (not faster ones), but more of them.This speeds a systems overall work load and makes it run smoother, but has negligible effect on FSX. It is my understanding that the only concession to multi-threading since FS9 (which had none) is that scenery is now loaded on a separate thread.This will help when traveling very fast and when turning, but otherwise has practically no effect on framerates. This is what I see on my twin CPU system.regards,Alan.

[Sesquashtoo 2,846]

You're absolutely RIGHT!After reading your post..and the replies, I went back to FSX...and took out the stuff you postulated was sucking up the CPU cycles.Right on the money!I got rid of: (tabs fully to the left and off)Marine Equipment (pleasure and ferry)Put Commercial A.I. at 33 percentTurned GENERAL Aviation full to the left (nothing)Put Road Traffic at 25 percentPut AIRPORT vehicles at MEDIUMPut all SCENERY sliders WEST, (smile), other than no AUTO GEN.The only exception to that was SCENERY DETAIL at NORMAL.With all the above, on a Pentium 4 3.4/ATI X800XT:I get 25 and UP!!!! FPS (Yesssssssssssssssir!) at 1,500 ASL and higher (ANY SCENERY, any part of the world)I get 12-19 on approach to MAJOR, DETAILED airports.I get 8-18 whilst on the ground at the majors, with all animation going on around me, including departure and arrival A.I.FSX is now VERY, VERY usable.Give my settings a try and you will love it. If you like what you see..then make sure to SAVE it as DEFAULT.cfgCheers!Mitch R.

[Guest BOPrey]

None of this do me any good. With water set to Mid 1x, and nothing matters until I turn off autogen completely. FSX stays at 8fps over New York City.

[Guest smarti05]

>None of this do me any good. >>With water set to Mid 1x, and nothing matters until I turn off>autogen completely. FSX stays at 8fps over New York City.crikey you get 8fps i only get 5 thats a 60% improvement!!I am beginning to think that this is one version of flight sim that will quickly die. The singl core cpu speeds for none overclocked systems will possibly never be fast enough.I cant see fsx flying of the shelves now.