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Guest PaulL01

Vsync=on/off performnce results data....

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Just to reconfirm what has been a long standing result ever since Matrox included the Vsync=off feature in their old Mystique video card and as a result stirred up their competitors into making it available in their cards as well and is available down to this very day and the recent interest in this setting I am posting some testing results for your review.Please Note:As in the previously posted topic concerning Vsync and a possible performance increase by turning it on: If you are using Microsoft approved

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Paul...an excellent analysis and a great post! I've been in this biz (flight sim guy) for many years, and this has been a perennial favourite topic of discussion. I wish I could be more technical in what I am about to say (since I am a technologist) but sadly, we cannot know everything, so here is my layman's understanding:As to why you see lower frame rate with vsync on, it is due I believe to the fact that vsync is a component of your refresh, and the resultant FR will always be some multiple of the active rate. I am not sure, but in the end it could be summed up like this:No vsync, and 58htz refresh, FR could be 58.Vsync, and 58 hertz refresh, FR would me locked at a multiple of that value, and would probably work out to something less than the existing FR. This is in line with the old adage that your FR cannot exceed the refresh when vsync is on.I'm sorry this sounds so "stupid" and perhaps you already know all of this, or I know nothing, but I had to reply to your nice post! :)Best btPS...Since I am stammering here, let me cut and paste from someone else

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Hi Paul,Good analysis... What was the average framerate between the two?And while it can't be measured, what was your "fluidity" feel in both tests? With VSync on, it looks almost identical to what would be the case if the internal framerate limiter was enabled. Doing so increases the fluidity of FS, so I'm wondering if you experienced the same increase with VSync on and the FS's framerate limiter off. If so, it sounds like FS might be transfering textures throughout the short flight even though they should have been preloaded (for such a small flight area) prior to start.http://members.rogers.com/eelvish/elrondlogo.gifhttp://members.rogers.com/eelvish/flyurl.gif

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>Hi Paul, >>Good analysis... What was the average framerate between the >two?I'm on the fly right now Elrond so I will have to get back to you on that but it looks like 23 vs. 33 >>And while it can't be measured, what was your "fluidity" >feel in both tests? With VSync on, it looks almost >identical to what would be the case if the internal >framerate limiter was enabled. Doing so increases the >fluidity of FS, Not at all,as the graph shows there seemed to be jumps and peaking much more abrubt with Vsync=onBut let me do a few more test and observations later.>so I'm wondering if you experienced the same >increase with VSync on and the FS's framerate limiter off. >If so, it sounds like FS might be transfering textures >throughout the short flight even though they should have >been preloaded (for such a small flight area) prior to >start. >Textures where preloaded I can assure you, as there was no waiting and the flight had been run many times to verify the results.As Vsync usualy cuts the FPS to a third of refresh rate or even more in some cases the results look very predictable considering that, here is a great old source (1998) of info that you may enjoy reading much of it still seems to hold true:http://www17.tomshardware.com/graphic/98q4...7/index-02.htmlI will get back to you some time this evening.Take care,

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>As in the previously posted topic concerning Vsync and a >possible performance increase by turning it on: >If you are using Microsoft approved

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>>As in the previously posted topic concerning Vsync and a >>possible performance increase by turning it on: >>If you are using Microsoft approved

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