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View Full Version : V-SYNC or no V-SYNC?


zoomy942
02-24-04, 01:29 PM
i have an LCD monitor and i have never used v-sync before. but i will if the wizards here at nvnews think it would be best? what say you?

i love frame rates, but since i have a great card, thtas not the issue.

Gator
02-24-04, 01:45 PM
I use VSYNC, helps prevent choppiness

stncttr908
02-24-04, 01:46 PM
It definitely looks much better. However, if you have a graphically intensive game that varies greatly in fps, it might appear that your display is stuttering somewhat. What I mean is, since I usually run at a refresh rate of 85hz, if the card can manage at least 85fps it'll lock it at that. However, if it were to dip down below 85, v-sync will lock it at 1/2 that, say 42 for sake of argument, to avoid that "tearing" effect. This leads to what I see as a stuttering effect. For this reason I usually use it only on older games.

zoomy942
02-24-04, 01:46 PM
what kind of choppiness?

Gator
02-24-04, 01:51 PM
Originally posted by zoomy942
what kind of choppiness?

well... stuttering because of the fps shooting up and down, it kind of helps to level off the frames

not sure if I'm describing that right, but I like to use VSYNC when gaming, and turn it off when benchmarking to get those maximum fps hits

saturnotaku
02-24-04, 02:10 PM
If I have the option in a game to limit the frame rate, I will do so and leave vsync off. But for older games like Q3, the original UT, Oni, etc, I'll leave sync on because with my card I can use AA and AF and still maintain a very high frame rate.

Also, having triple buffering available will help prevent tearing with vsync off. In the OpenGL tab on ATI cards you can force triple buffering across all applications.

Nutty
02-24-04, 02:53 PM
hmmmmm

However, if it were to dip down below 85, v-sync will lock it at 1/2 that, say 42 for sake of argument, to avoid that "tearing" effect.

True, this is what triple-buffering is for. Instead of waiting for the next retrace, thus incurring the delay, the app starts rendering to a 3rd buffer, and when the vertical retrace occurs the drive then automatically displays the 2nd buffer, while the app is still rendering to the 3rd. Its stops the frame-rate going 85 -> 42 -> 24 -> 12 etc.. etc..

Also, having triple buffering available will help prevent tearing with vsync off.

Nope, tripple buffering without Vsync is pointless. Tripple buffering does not prevent tearing, v-syncing does. Tripple buffering just prevents the gigantic frame-drops when you cant quite match the frame-rate with the vertical retrace frequency.

I'd be inclined to say leave it off, but I'm not sure how the whole simulated retrace timing on lcd's and tft's work so I dunno. I dont know how, and in what order the screen is updated. Tearing is a problem with top - down scanlining. If you change the contents of the buffer while the screen is half-way through rendering you get different images in the top of the screen to the bottom, thus a tear in the middle.

Try it both ways and see which you prefer. Chances are you might not even get tearing, or you might prefer the solidness of a fixed frame-rate produced by vsyncing.

saturnotaku
02-24-04, 03:56 PM
Originally posted by Nutty
I'd be inclined to say leave it off, but I'm not sure how the whole simulated retrace timing on lcd's and tft's work so I dunno.

It's just as much a problem on LCD displays as it is on CRT. In fact it's probably worse because most LCDs have a "refresh rate" of 60 Hz (though depending on what you have you can force it as high as 75). Lots of CRT displays have refresh rates of 100+ Hz at 1280x1024 and 85 at 1600x1200. In certain situations, if you have vsync off, tearing is really horrible on LCDs.

Nutty
02-24-04, 04:04 PM
So LCD's are refreshed just like a CRT?
What about TFT's?

fingermouth
02-24-04, 05:16 PM
Saturnotaku, how is it going today in Naperville. Its doug here in Berwyn, I am some what comfused about Vsync whether i shoud iuse it or not. By defult its on Auto which for me is good. I play the FPS games at high res like MOHAA and its stull tears in the game even with in on, which is wierd cause every card i had since playing that game has always teared even with AA on or Vsync on. I use an 85 refresh rate.

Anyway nice to see you again finally warming up outside so i will be out and about this weekend maybe out their at tiger so enjoy.

saturnotaku
02-24-04, 06:40 PM
Originally posted by Nutty
So LCD's are refreshed just like a CRT?
What about TFT's?

I always thought LCD and TFT were one in the same. Anyway, notice how I used quotes around refresh rate. I can't explain the technical aspect of it, but LCD/TFT/flat panel displays don't have a refresh rate in the sense that CRT monitors do. I'm sure there's a Web site or two that explains why.

Saturnotaku, how is it going today in Naperville. Its doug here in Berwyn, I am some what comfused about Vsync whether i shoud iuse it or not. By defult its on Auto which for me is good. I play the FPS games at high res like MOHAA and its stull tears in the game even with in on, which is wierd cause every card i had since playing that game has always teared even with AA on or Vsync on. I use an 85 refresh rate.

Anyway nice to see you again finally warming up outside so i will be out and about this weekend maybe out their at tiger so enjoy.

For me it purely depends on the game I'm playing. Like UT2003/4 I use vsync off and don't really notice any tearing (when my frame rate is above 75 that is). But in Quake 3, I keep it on all the time.

Are you sure you have vsync forced on in your control panel? Both NVIDIA and ATI cards have the option to force it on or off. If you have it set to "auto" in the control panel, the application decides whether or not to use it. For Quake 3 engine games, there's a line in one of the config files that should read something like this:

r_swapinterval 0 (or 1)

0 - vsync is off
1 - vsync is on

If you force vsync on or off at the driver control panel level, this config file line is meaningless. But for auto, that's where it will come into play. You're probably getting tearing in MOHAA because you have vsync set to auto in the control panel but 0 in the config file. Adjust one or the other and you should be fine.

Actually, when I was out on break this afternoon I went to the EB Games store in Broadview (at Cermak Road and 17th Ave.). That store is the shiznit if you want hard-to-find Game Boy or other console games. I picked up a Game Boy Color version of Super Mario Brothers that I haven't been able to find at about 6 other EB and Gamestop (ugh) stores I've visited.

zoomy942
02-25-04, 08:48 AM
as usual, thanks everyone for all this info. i think i am gonna give it a try. i do see alot of tearing on my LCD, and i am curious to see how it cleans up with vsync. also, in the drivers, i have the option to render 1,2,or 3 frames. what would that do?

saturnotaku
02-25-04, 01:40 PM
Originally posted by zoomy942
also, in the drivers, i have the option to render 1,2,or 3 frames. what would that do?

Setting it higher than three can cause some major mouse lag in games. Setting it lower reduces performance ever so slightly. I've always left it alone.

Princess_Frosty
02-25-04, 05:54 PM
Tearing is an effect you can only *REALLY* see when you have a frame rate above your refresh rate, only then do you start getting multiple images displayed within the same frame, every frame.

When your frame rate is almost always below your refresh rate then you wont get much in the way of tearing, it still happens but its only ever once per frame and every few frames, not every frame.

Of course you can bump up your monitors refresh rate to help solve this problem, if you can get it nice and high then its better than v-sync, this obviously is just my opinion, also consider using higher video settings to cause your video card to slow down, obviosuly not to a grinding halt (below 30fps) but certainly below your refresh rate, which should be at least 75Hz at all times.

I have v-sync of for the most part, i have a very good monitor which can reach about 120-140Hz in 1600 1200, so unless im running a really old games i don't tend to get those sort of frame rates with the quality cranked up to max.

fingermouth
02-25-04, 11:44 PM
Originally posted by saturnotaku
I always thought LCD and TFT were one in the same. Anyway, notice how I used quotes around refresh rate. I can't explain the technical aspect of it, but LCD/TFT/flat panel displays don't have a refresh rate in the sense that CRT monitors do. I'm sure there's a Web site or two that explains why.

[b]

For me it purely depends on the game I'm playing. Like UT2003/4 I use vsync off and don't really notice any tearing (when my frame rate is above 75 that is). But in Quake 3, I keep it on all the time.

Are you sure you have vsync forced on in your control panel? Both NVIDIA and ATI cards have the option to force it on or off. If you have it set to "auto" in the control panel, the application decides whether or not to use it. For Quake 3 engine games, there's a line in one of the config files that should read something like this:

r_swapinterval 0 (or 1)





0 - vsync is off
1 - vsync is on

If you force vsync on or off at the driver control panel level, this config file line is meaningless. But for auto, that's where it will come into play. You're probably getting tearing in MOHAA because you have vsync set to auto in the control panel but 0 in the config file. Adjust one or the other and you should be fine.

Actually, when I was out on break this afternoon I went to the EB Games store in Broadview (at Cermak Road and 17th Ave.). That store is the shiznit if you want hard-to-find Game Boy or other console games. I picked up a Game Boy Color version of Super Mario Brothers that I haven't been able to find at about 6 other EB and Gamestop (ugh) stores I've visited.



Oh **** are u serious, where is it by in Broadview Square near the China Buffet or by the Washington Mutual bank tell me please. I like that store and they still have Dreamcast games too. We have to hook up if so i will go their on Monday if u want i will be their at 2PM im in the black leather jacket with goaty beird and im 6" 2. if u can let me know where its at and i studied how Vsync works so im in the clear know thanks for the help man appreciate it.

burningrave101
07-13-04, 04:54 PM
So tearing occurs even when your getting lower FPS then what your monitor is able to refresh at?

I turned v-sync off and i primarily play Morrowind. I run Morrowind at 1600x1200 @ 85Hz. Frame rates in exterior cells are usually like 30-40 fps. Sometimes higher or lower depending on what region i'm in. In a big city like Balmora they dip down below 30 fps.

You can set the max FPS in-game through the Morrowind.ini file. I have mine set to 85 fps.

Am i still going to get tearing or anything else by having v-sync disabled?

And does 85Hz = 85 fps or is it just close to that?

phantom1979
07-13-04, 08:54 PM
85 hz + Vsync will lock your max FPS at 85

burningrave101
07-13-04, 09:30 PM
85 hz + Vsync will lock your max FPS at 85

Does 85Hz actually equal up to 85 fps though? There has been alot of debate about it on different forums and some say that refresh rate has nothing to do with frames per second.

Can anyone explain?

phantom1979
07-13-04, 09:33 PM
try and run 2001SE with vsync set to always on and set your refresh at 100hz.... you wont go above 100 fps

burningrave101
07-20-04, 12:23 PM
I'm still confused as to if its better to disable v-sync if your not getting higher FPS then your monitors refresh rate.

I get like 30-40 fps on average in Morrowind with the view distance set to max at 1600x1200 w/ 4xAA + 16xAF.

Should i disable v-sync? What setting do you guys use on your CRT's and why?