We often neglect to get too involved in the discussion of what options people should always enable when they play games. Rather, we tend to focus on what we test with. Honestly, our recommended settings for playing the games we test would be very similar to the settings we use to benchmark with one very important exception: we would enable triple buffering (which implies vsync) whenever possible. While it's not an available option in all games, it really needs to be, and we are here to make the case for why gamers should use triple buffering and why developers need to support it.
Most often gamers, when it comes to anything regarding vsync, swear by forcing vsync off in the driver or disabling it in the game. In fact, this is what we do when benchmarking because it allows us to see more clearly what is going on under the hood. Those who do enable vsync typically do so to avoid the visual "tearing" that can occur in some cases despite the negative side effects.
We would like to try something a little different with this article. We'll include two polls, one here and one at the end of the article. This first poll is designed to report what our readers already do with respect to vsync and double versus triple buffering.
{poll 134:300}
After reading the rest of this article, our readers are invited to answer a related poll which is designed to determine if arming gamers with the information this article provides will have any impact on what settings are used from here on out.
First up will be a conceptual review of what double buffering and vsync are, then we'll talk about what triple buffering brings to the table. For those who really want the nitty gritty (or who need more convincing) we will provide follow that up with a deeper dive into each approach complete with some nifty diagrams.
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DerekWilson - Friday, June 26, 2009 - link
I do make the claim that it's always better, but just wanted to use one example for simplicity sake (the 300 fps example).at lower refresh rates, the general case for performance is still the same as double buffering without vsync (which starts rendering the same frame that triple buffering would start rendering) ... and it still has the smoothness and lack of tearing of double buffering with vsync.
james jwb - Friday, June 26, 2009 - link
what about when 120 hz LCD's come out and if a game can provide 120 fps as a minimum. surely double buffering is the best case here, or will triple buffering perform exactly the same in this case?JimmiG - Friday, June 26, 2009 - link
The reason double buffering still prevails is probably because when current 3D standards were set during the late 90's, video memory was at a premium.For example, at 1024x768 (standard resolution at the time), each buffer would take up 1.5 MB at 16bpp and 3MB at 32bpp. Not a lot today, but back then 8-16MB cards were the norm. If a game was designed so that VRAM usage would peak at 16MB, adding a couple MB's usage for another buffer would kill performance. So the general idea was that "Yeah, sure triple buffering is nice, but it uses too much memory", and that idea hs kind of stuck.
fiveday - Friday, June 26, 2009 - link
There are major advantages to using Triple Buffering, but a few points that explain why its not automatically adopted.One big one is lag. Now, if things are pretty well lag free under double-buffering, no sweat. However, there's no getting around the fact that by adding an extra frame, you're adding 1/3 extra processing time between the frame being drawn and appearing on your display. If the game's pretty lag-free already, you'll never know the difference. If the game is already prone to some sort of input lag, it's about to get worse. How much worse, depends on the game itself... and in some cases it can drastically soften up your controls. It can be tricky to predict how much impact it will have, if any... a point I'll return to in the conclusion.
Another issue is memory usage. In a perfect world, every system will always have adequate texture memory accommodate triple buffering. Is it a perfect world? Nope. And if your graphics card is getting thin on ram, get ready for a performance hit. How much? Maybe none, maybe a lot. Which brings me to my last point.
Whether or not you'll see these adverse affects from using Triple Buffering depends partly on the game itself, how it was written, and partly on your own system configuration. Now, the developers are responsible for their own software, but there's no telling what kind of system a end user is going to try to run the game on. These days, a 4670 graphics card and a phenom X2, while seemingly meager, are enough to get most games out there plenty playable... but there's still folks out there trying to run a game like Bioshock on a Radeon 9700 pro (what's SM2.0, they cry!?!). Lord forbid someone try to use their laptop to play a game.
By the way... SLI and X-Fire setups tend to HATE triple buffering.
So you see... the developers have a tough enough time as it is getting their games playable on an extremely unpredictable variety of systems. Triple Buffering, while it has its advantages, simply introduces further risk of poor performance on a lot of systems out there. Should it be automatically enabled? Nope.
But should it be available as an option? These days, I see no reason why not. The original Unreal and UT engines offered it as an option, and that was ten years ago. Bring it back for those of us who want to take a crack at it.
DerekWilson - Friday, June 26, 2009 - link
you are correct that SLI and CrossFire don't like playing well with triple buffering... but then there have been plenty of oddities no matter what page flipping method we want to use.but enabling triple buffering does NOT add an additional latency penalty over double buffering unless double buffering visibly tears and you are talking about the rest of the frame ... double buffering and triple buffering start rendering the same frame every time.
there is no inserted frame into the pipeline, as it's not a pipeline -- what you are describing is more like DirectX's default 3 frame render ahead which has much higher potential to add latency than triple buffering (when we are talking about the page flipping method and not just "having three buffers").
sbuckler - Friday, June 26, 2009 - link
If tearing is not a problem then you are better off double buffering with vsync off. Turn on triple buffering and you introduce another 16.6ms of display lag which matters in a fast fps.DerekWilson - Friday, June 26, 2009 - link
you do NOT automatically incur a one frame lag -- you have at most an additional one frame lag.as i explained, especially in fast shooters, triple buffering and double buffering with no vsync begin rendering the exact same frame even if double buffering without vsync switches to a newer frame at some point.
and when tearing doesn't "happen" (read isn't noticable) then that means the updated frames were not different enough to really matter anyway (otherwise you would see the difference).
the possible advantage of double buffering could be argued when a tear happens near the top of the screen, but whether this is a real advantage is debatable.
BJ Eagle - Friday, June 26, 2009 - link
with double buffer vsync and framrate just below 30 FPS ?I would go for double buffer vsync if there is not an equal penalty going below 30 FPS as there is when going below 60 FPS. Simply because I don't want to waste power rendering frames I wont miss...
Movie industry teaches us that 25-30 FPS is actually enough to fool our brains to perceive motion. But if the lag skyrockets with vsync af below 30 FPS I guess I would go with triplebuffer...
nafhan - Friday, June 26, 2009 - link
With a 60hz refresh rate, I think dropping below 30 will cause the same issues as dropping below 60. Vsync is going to update frames at intervals that divide evenly into the refresh rate. So, if 30 is not an option, then it will update every 20 frames.I think most people can tell the difference between 30FPS in a game and 60FPS. However, more than that really doesn't provide much benefit.
toyota - Friday, June 26, 2009 - link
a game is not a movie...