I have been happily flying FSX + SP1 on my Q6600 with only one problem:If I set the affinity mask to 15 (1111) so as to utilize all cores, FSX will crash to desktop within a minute or two. If however I use a setting of 14 (1110) FSX is steady as a rock with no blurries and very acceptable perfomance.I realise that most background applications will be using the first core and therefore it makes sense to prevent FSX from using this and allow it to run the cores 2, 3 and 4.Why should FSX crash when all 4 cores are utilised?TIA

Bumping.

What kind of performance are you getting with your Q6600?Did you overclock it?Bryan

See my post in the hardware sub forum. I didn't have any crashes using 4 cores, but I found better performance with my 2 core CPU, 6750.I didn't get a chance to try limiting FSX to 2 or 3 cpus.I dont know if its the OS or the game, but it didnt seem quite ready for 4 cores when I tried it. I'm sure some here will post success stories soon..

Although this is hardly my field, it could be the game itself.From what I gather the game needs to be optimized for 4 cores.The upcoming game, Crysis, is said to be optimized in such a way; in fact there is a video showing Crysis being run on 4 cores with a Penyn/Yorkfield setup, with some nice dev commentary, here:http://ve3d.ign.com/articles/804/804486p1.htmlCheers,Bryan

FSX uses all 4 of my cores. I just checked all 4 boxes in task manager.All read over 85-90%?Get very good performance with SP1.Buck

Buck interesting, if you leave task manager open to watch the cores does it always use about 85% ?With the Intel quad, it would go up to 100% loading but then flying would be jumping from usually around 25% to 80% or so, with performance issues. It just lacked the smoothness I get with the core 2 duo that always stays up near 100%.That was a 6700 Quad on a Asus P5K Deluxe.

If you read and understand the guidance I gave about SP1 and how it uses the cores, that makes perfect sense.Initially, the terrain texture synthesis will use all available cores. as the terrain textures load, the usage will drop. As they load, usage will go up. What forces a load? As you turn, climb/drop, or fly straight - you cross tile boundaries and force a load. Then the cores are used again. Same for Autogen batches. Nothing mysterious, nothing unusual, all expected.

>If you read and understand the guidance I gave about SP1 and>how it uses the cores, that makes perfect sense.>>Initially, the terrain texture synthesis will use all>available cores. as the terrain textures load, the usage will>drop. As they load, usage will go up. What forces a load? As>you turn, climb/drop, or fly straight - you cross tile>boundaries and force a load. Then the cores are used again.>Same for Autogen batches. >>Nothing mysterious, nothing unusual, all expected.Phil - the unexpected was better in flight performance on a Core 2 Duo, than on the quad at the same speed? It was clear to see, the loading of autogen on the quad was not as smooth, and graphics issues were clear. Those Q6700's run very very hot in a P5K, up to 70C+. I hoped a quad may outperform the duo, but it disappointed in my 3-4 hours of testing. The only difference in the setups were the CPU's and with the quad I used the newer 8800 video driver.No worries here, the new core 2 duo system with FSX is amazing.

In terms of relative usage, that actually makes sense. Given there is only 1 "spare" core, its kept more loaded than 3 "spare" cores. In terms of overall perf, a subset of people still have problems with quad cores and DX10 hardware were it doesnt perform as we might expect.

>If I set the affinity mask to 14 (1110) FSX is steady as a rock>with no blurries and very acceptable perfomance.>>I realise that most background applications will be using the>first core and therefore it makes sense to prevent FSX from>using this and allow it to run the cores 2, 3 and 4.>TIAThanks, TIA, for suggesting only using cores 1, 2, and 3 for FSX, and leaving the system to use core 0. Setting the AffinityMask to 14 has finally solved the relentless stutters and macro-stutters that have plagued my system since SP1. (QX6700 Quad, 8800 GTX 768mb, 4 gb system ram).I cannot believe what a difference it has made: fluid, stutter free, sliders maxed out. It's gone from a nasty slide show on even minimal settings, to a real joy to behold. :(From now on, the system can have core 0. FSX gets cores 1, 2, and 3.Thanks again mate.Carey F

How do you set the affinitymask to 14?

http://dev.fsinsider.com/tips/Pages/SP1How...uInstallIt.aspxAbout 3/4 of the way down it explains what to do...

Just upgraded to a quad core processor. Tried the affinity mask trick and i still get constant stutters. It's weird, it will go from 40 to 10 and back to 40. I have a 7900GT, 3 GB of RAM and I'm running FSX off a SATA drive. Sometimes it runs like butter, but then it starts to stutter, especially in spot mode. Any ideas?Eric

Recently got a Q6600 system with Vista and an 8800GTS 320 card. Got it because my other PC went on the blink so had no choice. Did not get it for FSX.Anyway after having the new PC for a month now I finally fired up FSX today after reading this thread. Took me long to do it because I just could not bear more disappointing performance as with my old P4 system.:-) I should mention the install and SP1 update went without a hitch. No activation problemsI bumped up the default settings a bit and set FPS target to 30 and to my surprise, my first flight around KMIA with traffic at 30% and autogen normal, was quite smooth and nice. I had set affinity to 15 prior to the flight as per PT's blog but now I will reset to 14 and see if it gets even better as mentioned here. The water is absolutely stunning at 2 I did check task manager and all 4 cores were being used around 60-80%. I also did not turn off any background services like anti virus etc. The flight was 30 minutes in the 737 at 5000feet so not much to go on. I will do more long hauls in different areas to see how it performs.But so far it looks encouraging and I can get back to some flyingI may even buy ActiveSky for fSX..it was great for FS9 which I did not bother to install on the new PCJust thought I would share this experience and thanks to the OP for starting itBill