What exactly is VSync

[BDawg]

And why does turning it off make games faster? What is the down side to turning it off?

 

[Workin']

Vsync means synchronizing the rendering of display frames with the vertical refresh rate of the display mode you have selected. What this means is that your frame rate will never be higher than your vertical refresh rate. So if your display is set to a 85 Hz refresh rate, you will never render more than 85 frames per second, even if your graphics card is capable of much higher rendering speeds.

If Vsync is off, then your graphics board will render frames as fast as it is able, and send them off to the display whether the display can draw the whole thing or not (it takes 1/refresh rate seconds to draw a whole frame). So you can end up with partially drawn frames being replaced with new ones. This is not always bad, but sometimes there is a tearing effect (it looks like a rip across the display) when the frame-to-frame changes are large. Otherwise it is not noticeable, and most people agree that the occasional tearing is worth the often times large performance increase.

 

[BDawg]

Well then, here's a follow up question:

Does my systems refresh rate affect my fps in any way? Is it better to set a lower refresh rate or a higher one?

 

[BFG10K]

Does my systems refresh rate affect my fps in any way? Is it better to set a lower refresh rate or a higher one?

Absolutely. Your monitor's refresh rate directly affects the maximum framerates (which Vsync controls). Of course you still have to consider the refresh rate setting of the game and the refresh rate of the video card when running in 3D mode.

Things can become complicated if you start adjusting too many variables at once.

 

[The Wildcard]

Just keep it simple....Vsync off = good fps, Vsync on = bad fps.

 

[pen^2]

The_Wildcard, that would be deceiving since the minimum framerates (which is what really matters) would be the same, thus no visible slowdowns for having vsync on.

 

[BDawg]

I'll reword the other question...

If my refresh is set at 85 Hz, and I can acheive 60 fps in this config, does changing to 100 Hz have any effect on this?

Should I always keep my refresh rate at adapter default, optimal, or whatever I want?

 

[pen^2]

goin from 85 to 100 only increases the maximum fps allowed; 60fps is good enuff IMO and extra gains from upping the refresh rate wont make the game any smoother. a noteworthy fact is altho you get lesser eyestrain at higher refresh rates, anything above 85hz reportedly results in a bit blurrier image.

 

[RayZor]

Workin' ! Thanks for explaining that

 

[Workin']

<< If my refresh is set at 85 Hz, and I can acheive 60 fps in this config, does changing to 100 Hz have any effect on this? >>

No. If the highest frame rate your card can achieve is 60 fps, then there will be no difference going from 85 Hz to 100 Hz. Which means that having Vsync disabled or enabled will give the same results, fps-wise. But 100 Hz should totally eliminate any flicker (not that you can notice any at 85 Hz), but that's a seperate issue from frame rate.

 

[Phuz]

Never knew..

 

[Grminalac]

Well thats not exactly true, I am assuming your 60fps is your average, at any given time your framerate may jump in either direction; running slower when more rendering is required and faster as well- depending on what you do in the game. At some points during little action you may very well be getting 85fps. By increasing your refresh rate you will raise the ceiling to 100. You would probably see a average framerate increase since many of the variables calculating the average would be 100 instead of 85 (when standing around and during little to no action). But raising the refresh rate won't make the game any smoother during heavy action when a lot more rendering is required, but it makes your system look better when comparing framerates to others.

 

[shurato]

Doesnt VSYNC effect opengl games also? I have it turned on and i get well above 100fps in timedemo's in quake 3....plus its only an option to turn off and on in the direct3d section of the ati control panel.

 

[faye]

am i right:

If Vsync is on, then the FPS should be locked to 60fps(if i set 60hz),
A human eye can't see anything above 30FPS, so 60 will be fine but not only that,

When i videocard that only has to render 60fps not 100fps, the job for it is lesser, so is it a good way to keep ur card cool?

 

[Workin']

Grminalac - Not to nitpick, but I said if 60 fps is the highest your card can achieve, which means it can't do any higher, then you will see no difference. But what you said is indeed correct - your average framerate may go up with a higher vertical refresh.

shurato Yes, it affects OGL and D3D. In my ATi control panel the option to turn it off is under both tabs. I have a Rage Fury Pro using the latest Win 98/Me driver set.

faye

<< If Vsync is on, then the FPS should be locked to 60fps(if i set 60hz) >>

Sort of - in that case your framerate is limited to 60 fps, but lots of frames may be rendered slower than that, so in that sense it is not &quot;locked&quot;. By the same token, if you disable Vsync to let the card run as fast as it can, some frames will be rendered at an instantaneous rate of say 100 fps, but other more complicated frames may render significantly slower. But the average rate would be higher. In any case, limiting the performance of the card won't make it run significantly cooler, and then you may be giving up a large chunk of the performance you paid all that money for in the first place.

 

[BFG10K]

A human eye can't see anything above 30FPS

Stop talking BS Faye.

 

[Workin']

24 fps is generally regarded as the minimum fps needed to give the illusion of smooth motion. That's what movies and DVDs use. But more fps is better when it comes to fast-twitch shooter games like Quake, etc.

 

[OneOfTheseDays]

For a long time, i used to believe that vsync off was better. However, this is not true. If your monitor can run at a refresh rate of 85hz or higher, then i suggest you keep vsync on. In quake 3, for example, i noticed less fluctuations in frame rate with vsync on. Vsync on will also get rid of annoying tearing errors. I suggest you give both settings a try and see what works best for you.

 

[Witor]

<< 24 fps is generally regarded as the minimum fps needed to give the illusion of smooth motion. That's what movies and DVDs use >>



Dont know what the fps is for DVD's, but the reason why 24fps is the fps for movies is because each image is blurred, try freeze framing a VHS tape, note the blurred look of each frame, at 24 fps these blurred images appear smooth.

Like you mentioned correctly, more FPS is needed in games like q2/3/ut, because as with all computer generated frames, they are not blurred, therefore much higher fps is required to achieve &quot;smooth&quot; motion. An easy way to demonstrate this is to load up q2 and type &quot;set cl_maxfps 24&quot;, then try the same but &quot;set cl_maxfps 60&quot;. The equivalent Q3 command is &quot;com_maxfps&quot;

Higher FPS also does help if you ever get hardcore with FPS games, along with higher mouse hz rates it can lead to much better aiming/control. I know

 

[BDawg]

Is there a way to archive informative posts like this one?

 

[Workin']

I think you can have IE save the whole page. Or, you can copy the text into a word processor or text editor. And probably some other easier/more creative solutions, too.

 

[BDawg]

Well I mean like an archive section for the forum, where the board can store common questions and very informative posts...

I know how to save it for myself ^_^

 

[Workin']

Ooops - sorry, you never know when someone asks a question like that...

All the threads are archived for some amount of time - you can search them from the search page - I think that's about as close as you can get for what you are asking, but I'll have to say it's not that easy or organized.

 

[BFG10K]

24 fps is generally regarded as the minimum fps needed to give the illusion of smooth motion.

Perhaps for movies because of their blurring trickery and that fact you are not interacting with them in any way. Not for 3D games though, no way. 24 fps is unplayable in a 3D game.

 

[Workin']

<< 24 fps is unplayable in a 3D game >>

Ha! Tell that to my Pentium 60 and Voodoo Graphics card! You're spoiled