i ran across a tweak here: http://forums.guru3d.com/showthread.php?t=318079it has something to do with win 7 core management. i've tried it and for some reason fsx doesn't seem to like AA anymore (fps is low) - on the other hand i'm able to run at solid 60 fps at very dense autogen, i'm not sure if it's because of the core tweak, could be.what do you think of this?[i]PROBLEM: Core Parking is a feature of Windows 7 that is causing rare performance problems. I don't notice it on my home i7 / Win7 system but some people are getting microstutters and odd behavior in certain programs. Without the following " tweak" you may see CPU spiking in your programs and Windows Task Manager - some CPU cores will be "turned off" / "parked" depending on load and they will be dynamically turned on or off and dynamically loaded up or down as the system deems necessary - the scope for glitchs / pops / clicks / droputs etc.... in such an environment is simply enormous. To the best of my knowledge, there is no known "switch" to turn it off - no utility I am aware of to "tweak" it off.****FIX:- Go to Regedit- Select Edit > Find... and find this key: " 0cc5b647-c1df-4637-891a-dec35c318583 "- Within this key, there is a value called: " ValueMax " This value represents the % number of cores the system will park- Change the value of " ValueMax" to 0 so that, it matches " ValueMin "- You will have to find the key a few times and repeat the process for each time it is found - the number of instances will depend on the number of power profiles in your system. To do this go back up to Edit > Find Next. (I had 3 instances of this key in my registry.)- Do a full shutdown and power-off and cold-re-start.****RESULT: Better load balancing across all you CPU cores - no spiking - in Windows 7 Task Manager****COMMENTS:Quote:Thanks for the info! I upgraded to Windows 7 just this Monday, and I noticed a pretty good increase in general performance and gaming performance; however, I did have some rather annoying micro-stuttering. The removal of core parking has fixed that problem.Quote:Wow you sir rock. This fixed my FPS issue in games with windows 7. Soon as I disabled core parking, my FPS is back in its full glory. This info should totally be sticky'd or contained in a tech support stickyQuote:I tried disabling Intel Speedstep, disabling Catalyst AI for my Radeon HD 4870s, and nothing worked until I edited these registry keys. Now I'm getting great FPS in games with no spiking. Thanks!Quote:this trick fixed my problems with stuttering and laggy fps[/i]http://forum.cakewalk.com/tm.aspx?m=1861804

Zorg:In no way am I one of the "experts", but I can tell you that I have implemented this and disabled core parking in Win7. (I followed the alternate procedure in this link: Alternate Procedure, which allows you to disable/enable core parking through selection of a custom power management plan - USE AT YOUR OWN RISK!). Although the rationale makes sense to me, disabling core parking has not exactly knocked my socks off. Perhaps there is some marginal benefit, but I have a hard time seeing it. (I am running FSX in DX10, BP=400M (not 0), TMB=110; FFTF=.20; ATI 4870X2 - stutters are generally minimal except in high cloud density settings. Am too lazy to run benchmarks.) Still, I have not noticed any ill effects so I am leaving core parking disabled for now. I would be interested in hearing about others' experience with this.Major V

Same here.. no gain in FPS (nor perceived or real) another placebo thing :) like the L2 cache tweak

ok, thanks. i have disabled the tweak again. fsx seems to run just as good without the tweak.

You might not see fps increases, but what about overall smoothness and stability?

Run FSX and check your cores in task manager. All 4 of my cores (no hyperthreading) are running like banshees all of the time without the tweak.I think that it is related to speedstep.jja