From MS:Method 4: Adjust target frame rate to unlimitedIf the frame rate is limited to a specific number, it does not spend any more resources than the resources that are required to render the selected frame rate.To adjust the frame rate so that the computer can use all the resources, follow these steps:1. Start Flight Simulator 2004.2. Click Settings.3. Click Display.4. On the Hardware tab, move the target frame rate to Unlimited.5. Click OK, and then test the settings.http://support.microsoft.com/default.aspx?...kb;en-us;823629JohanA LITTLE LESS CONVERSATION, AND A LITTLE MORE ACTION PLEASE!HELP:http://support.microsoft.com/?kbid=238882

Although I think an MSFS dev team member commented on this in a blog, I always felt that my FS2004 performance was better--even on a P3/800--with my target frame rate at unlimited. In FS2002 the opposite seemed true with the main benefit being an elimination of "dynamic blurries" that would happen at higher speeds.My understanding of locking the fps down (before some of us noticed in FS2002 that it helped with keeping blurries down) is that its purpose was to even out the fps, so we wouldn't "sense" changes in fps that can happen if the fps fall off by 50, 60 pct. The reasoning being that 15 consistent fps is better than 25,15,20,17,28,15.... and so on--thus locking them to 15 would make things look smoother to the end user.CFS 2 had a feature that wasn't implemented in either FS2002 or FS2004, although there's still a reference in the cfg file. In CFS 2, you could have the sim adjust the scenery detail based on target frame rate--it was called "Auto LOD". In a sky full of flak and dogfighting aircraft, one didn't care about what was on the ground much, and enabling auto LOD allowed CFS 2 to, on the fly, optimize fps based on a cutoff value. Again, that's referenced in both the FS2002 and FS2004 cfg, but it's never worked--I've never seen detail adjust based on anything I've done with the fps slider or any hack I've made to the cfg.-John

Hi John,Isn't introducing the "blurries" (or actually low res textures to replace high res ones) doing effectively the same as the Auto LOD that CFS2 has? I might have all of this wrong, but that's what I thought was heppening. Maybe you're referring more specifically to scenery complexity. In never had CFS2, but can see how you wouldn't care about what scenery looks like when in a dog fight :)Bruce.

"Maybe you're referring more specifically to scenery complexity." Yep, I should have mentioned that more clearly, that CFS 2 adjusted scenery complexity--I can't remember in what order, but I believe it started with building density. As for blurries, my first card with FS2002 was a Voodoo. I couldn't see sharp textures at all. Then I moved to a 64 Meg GeF 2.... Textures stayed fairly sharp as long as I kept the fps locked around 25 or so, but they tended to blur with complex aircraft and/or moving fast through scenery (like 600kts plus). With my 128 meg card, dynamic blurries are gone altogether in FS2002 and pretty rare in FS2004. The only reason why I think I get any at all in FS2004 is I have more complex aircraft installed in that sim, combined with my using spot view a lot more given the eye candy FS2004 has hooked me with :) FPS lock did improve dynamic blurries when I had 'em in FS2002. If I locked down to 15 fps, I could keep the textures sharp even with the Voodoo sometimes. FS2004 doesn't seem to care about fps lock if I try to "self induce" dynamic blurries by slewing quickly over the terrain--fps locked or unlocked, it maks no difference on my system.-John

I have everything maxed out and frames set to unlimited. I found by locking a certain rate, regardless what it was, I suffered a fair amount of stutters. They weren't enough to be a bother since I was getting great scenery in return. But unlimited, which BTW did NOT change a consistant 29-39 frame rate, elimiminated all stutters.My $.02Bob

With my current machine my experience is the opposite, when I don't lock at 20 especially with complex aircraft I get stutters. However on my old pentium III machine fs9 always ran better with frame rate unlimited. So it is different on each system. Currently use Nvidea 6600 and used ATI 9250 on my old machine, don't know if this is a factor.

Yes, I notice stuttering when I set it to unlimited as well. However, I find that locking the frames at any reasonable level (even if its higher than the average fps you might get with it unlocked) eliminates the stutters. For some time, I've locked it at 25fps becuase that's about what I get when I unlock it on average. However, I've found that I can lock at 30 or 35fps, not notice any stuttering at all, and actually find that textures seem to load more quickly - specifically when I switch back and forth from the external, or 2D panel to the VC the VC textures load considerably faster with the frames locked higher...

Gentlemen, the reason the slider is there is to allow you to adjust it for your specific machine and circumstances... ;)There is no "one size fits all" answer to the question!

That's absolutely true. :) It's just that the conventional wisdom has always been to fly around for a bit, see what kind of framerates your system is able to maintain with the lock off, and then lock the framerate at that average or even slightly lower. I'm just pointing out that you might get better performance locking the framerate a bit higher than that average...but of course, everyones system is different and there are very few hard and fast rules that apply to all of us...

As I recall, the developer blog said that there were multiple threads running in FS, one of which was responsible for loading textures and doing scenery. So if the frame rate was locked then there'd be time for the threads to work. Sounds reasonable enough to me. What we need is a way to benchmark FS consisently, like most FPS games.Run the same flight weather etc over and over again and produce a graph of frame rates. So we can tweak and know if it actually helped or hurt.

Me too. I set my frame rate to unlimited and had studders. I then set it back to 25 and all is well. Who knows.JimCYWG

In one thread I read it was suggested to lock your frame rate until your V was 1 or less " <001.0> V: 0.1% ". This is how I lock my frames at a certain setting. The proof of the pudding is to look out of the side window at 1000 or 2000 feet and focus on a roof top as it passes by the side window. It should pass by, while watching it, micro stutter free.