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Guest philstix

Isn't 100 Percent CPU normal for FS9?

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Hi,I've noticed several posts in the forum from people complaining that some addon or other has increased their CPU usage to 100%. Isn't that normal? My P4 3.2 GHz CPU is always at 100% from the moment I start FS9 (not automatically loading a flight, just displaying the opening window where I can create a flight or whatever) until I shut it down. It's always been like that since I first installed FS, before I installed any addons.If it shouldn't be 100% all the time, then how do I get it to reduce CPU usage?My system, in case it's relevant:P4 3.2 GHz CPU1 Gig RAMLeadtek Nvidia 6800GT 256Mb video cardWindows 2000Phil

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Hi Phil,Short answer is yes, although I have never really understood why.Mike

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I think it's kinda like keeping the plumber at your house all the time. The *instance* a pipe leaks he's working on it. But if you let him go, his scheduling may not allow him to return immediately.I discovered playing in DX9/XP that if I released the CPU, it might not come back within as much as ~50 milliseconds - that's long enough to throw off a 20 FPS schedule. So I used the multimedia lib timer thing and just kept checking it in a program loop until the time was up. Since it was a loop, 100% CPU.That would be my guess. But maybe I don't know of another mechanism in XP to schedule better. Also I'd bet Vista has taken care of this.

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On my single processor main PC FS always has CPU usage at 100% although it doesn't seem to cause a problem running many other programs at the same time. But if I run FS on my dual processor laptop the CPU usage drops down to 50% approximately. I guess you would expect that.Rob Elliott, EGPE InvernessPSS Airbus Support andAirbus Fleet Training Captain, British Airways Virtual airbus@speedbirdonline.co.ukhttp://www.speedbirdonline.co.uk/airbus.htmlhttp://www.bavirtual.co.uk

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Ok, thanks for that. Now I know I shouldn't to be worried about the CPU usage.(I'm sure I'll find something else to worry about before too long...)Phil

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Okay, after reading this I'm concerned. Would FS9 perform better if I disabled "Cool'n'Quiet" for my AMD dual core processor?

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Hi,"Would FS9 perform better if I disabled "Cool'n'Quiet" for my AMD dual core processor?"I haven't noted any effects on performance while running FS9 whether "Cool 'n' Quiet" is running or not. I think this is because this feature is designed to kick in while the CPU is idling and there's not much chance of that happening anytime while FS9 is running!However, I did spot something a while back (and posted my findings in the FSX forum) whereby "Cool 'n' Quiet" can cause the hardware detection routine, specifically the CPU speed, to misdetect when FSX is run for the first time following installation or following deletion and subsequent rebuild of FSX.cfg. This results in the wrong values being set for the parameters 'ProcSpeed' and 'PerfBucket', i.e. they may be set far too low. This results in the initial sim settings being incorrect for the local hardware running FSX. The trick is simply to disable "Cool 'n' Quiet" in the BIOS temporarily until the correct values have been established in FSX.cfg.Actually, for those that are aware, 'ProcSpeed' and 'PerfBucket' can safely be ignored as we all override the resultant 'recommended settings' anyway. However, these two values do provide a reasonable starting point before the inevitable tweaking begins. I am sure the reason for their inclusion was to help all those casual simmers out there to achieve the best performance out-of-the-box with the minimum of effort.Mike

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