to v-sync or not to v-sync?

xxcoop42xx

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hey everyone, i was wanting to know what v-sync is/does so searched around the net and got myself educated on the matter but im confused. my understanding is its a limit of the graphics card to never go above the refresh rate of your monitor which equals fps, like a 75hertz refresh rate = graphics card limited to 75fps? thats my understanding of it. if im wrong someone please correct me. but my question is with dual graphics cards, is v-sync needed? should i use it? also i read that only really applies to crt monitors and not lcd even though lcd has refresh rate the article said it really doesnt apply to lcd. since ill have SLI configured graphics soulution, the image on the screen is split in half and one card does the top and the second does the bottom so i should have no tearing or ghosting issues, right? again correct me if im wrong. all replies/corrections appreciated.
 
you dont need to turn that on unless you have tearing of the image I never use vsync since I never had that problem and I feel difference from 60fps to 150+ when I play css.
 

Nils

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Hey,

I'm not quite sure about what it does exactly, but I think it synchronizes your video card's frame output with the moment that thay are displayed on your screen, so your display will always be ready to display a frame at the same time that it gets outputted by the GFX. My explanation can be wrong, but actually it doesn't matter how it works, but more important is what the result of it is.

Probably you will already have noticed that when moving around in a game, the image gets 'torn' apart in horizontal strips. This happens when v-sync is disabled. Enabling will let that disappear, but it will cause game lag, meaning that your response will decrease. A good point about v-sync is that it also serves as a kind of frame-limiter, which can improve gameplay.
However, I recommend that you disable v-sync in games that have a build-in frame-limit, like COD2 & 4, doom3, quake4,...
If the game hasn't got that limiter (like most games) it's up to you to decide whether you want a constant framerate (v-sync on) or a high game response, which is mostly needed in first-person shooters (v-sync off).

I hope this helped
 

xxcoop42xx

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well im going to be gaming on a 19" ws lcd prob around 14x9 resolution. so i wouldnt need to turn on v-sync? and my monitor has 5ms response time.
 

50bmg

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I never use v-sinc. I run COD4 at 130fps consistantly. I see some tearing on a rare occasion, but not anything that bothers me. I prefer to get my FPS as high as possible, so that the times it does drop, i am still above 60fps.

When i use v-sinc, i seem to notice poor quality and lower fps. Lower than the v-sinc setting.

If the tearing bothers you, than use it. If it is not a problem then dont. I would start with out v-sinc.
 

Nils

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That's the wrong way of thinking. When you want to get the best gaming comfort, you do not want to get the highest framerate, but you want to get the most constant framerate. The human eye only detects frame drops which cause a game to stutter. So playing a game at a constant 60fps is probably more comfortable than playing at frame drops from 130fps to 70fps :ouch:
 

50bmg

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That is my point. I consistantly play at 130. My fps very rarely drops to 60. The point is, i am always playing at a higher fps than my v-sinc can handle. So i turn it off.

Like i said, when i enable v-sinc, i notice a performance drop. Not just the lower fps that is locked in by the v-sinc, but an overall drop.

As long as the tearing is less of a problem then a constantly dropping fps, then i will go with the higher fps.

The rare occasion i see tearing, is only when a flash grenade goes off in game. I never see it any other time.

I know they say the human eye can't detect over 60fps, but personally, the smoother movement in high action environments is much more important and i do notice that.

If he sees a lot of tearing and it is problem then he probably need to enable v-sinc or lower some high settings.
 

xxcoop42xx

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well nils, ill be playing gears of war and halo2 and probably try crysis. thats just to start with (GoW is coming with pc). so i guess mostly fps games. and ill be using dual 9800gt in sli.
 

Nils

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In games like that you want lots of response, so I would not use v-sync. For more info on how to get the best gameplay, read my first post.

PS: The framerate setting in the COD4 graphics menu is NOT a framelimiter. It determines at which fps v-sync must run. Disable v-sync and fps will be as high as possible (not good)