What the hell is smart v-sync

Just curious and this is for the BFG edition. Just started playing the game and it seems to tear with or without smart v-sync. I'm one of those screen tearing nazis who also hates mouse input lag. Looks like this game can't be played without good old fashion v-sync enabled, so go-go input lag! :(

My admittely basic understanding of smart v-sync is that it goes something like this.

Say you have a display running at 60Hz and you're running a game where the target framerate is 60 frames per second, if you're getting 60 frames per second or higher, smart v-sync enables to prevent screen tearing, but if you're getting 59 frames per second or less, smart v-sync turns off to maximize framerate.

So basically it's nVidia's adaptive v-sync. Why didn't they just call it that and save people the confusion? Strangely, though, I still see ample tearing at the bottom of my screen with smart v-sync enabled, even when I'm managing 120fps on my 120hz screen.

Does your graphics card support adaptive v-sync? It sounds like setting the v-sync preference to smart causes adaptive v-sync to be used if your graphics card supports it, but will cause v-sync to simply be turned off if your graphics card doesn't support adaptive v-sync.

VSync
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The new "VSync" option in the video settings menu allows you to remove
screen tearing. There are three options: ON, OFF and SMART.

When VSync is turned OFF you may experience screen tearing.

When VSync is turned ON you should not see screen tearing. However,
any time your frame rate drops below 60 frames per second you will
get a sudden more severe drop to 30 frames per second. This is how VSync
inherently works. If your computer cannot maintain 60 frames per
second and you miss the synchronization to the vertical retrace of
your monitor then you will miss a whole frame and synchronize to
the next frame instead.

Some graphics drivers now support a so called "swap-tear" extension.
You can try using this extension by setting VSync to SMART.
If your graphics driver supports this extension and you set VSync
to SMART then RAGE will synchronize to the vertical retrace of
your monitor when your computer is able to maintain 60 frames per
second and the screen may tear if your frame rate drops below 60 frames
per second. In other words the SMART VSync option trades a sudden drop
to 30 frames per second with occasional screen tearing. Occasional
screen tearing is usually considered less distracting than a more
severe drop in frame rate.

If your graphics driver does not support SMART VSync and you set VSync
to SMART in the video settings then RAGE will automatically fall back to
turning VSync OFF and you may experience screen tearing. The "swap-tear"
extension is brand new and may still present some issues on certain
graphics hardware. If you experience any problems using SMART Vsync
then set VSync to either ON or OFF. We are actively working with the
graphics hardware vendors to improve the "swap-tear" extension.

If changing VSync in the RAGE video settings menu does not appear to
make any difference then make sure you are not overriding the VSync
setting in the graphics vendor control panel. You can find the
graphics vendor control panel by right-clicking on the Windows desktop
and selecting the " control panel" option from the pop-up menu.

If you force VSync to the 'on' setting in the graphics vendor control
panel then you should not see any screen tearing in RAGE but you may
get a more severe drop in frame rate if your computer cannot maintain
60 frames per second.

If you force VSync to the 'off' setting in the graphics vendor control
panel then you may experience screen tearing no matter what setting you
use for the VSync option in the RAGE video settings menu.

Yep, GTX 670. Handles the game flawlessly.

I dunno, I'm still optimizing and fiddling with settings. It seems like it tears with smart vsync at one moment and the next it won't. I think I'm gonna just chalk it up to the game's engine. I've read DooM 3 is a pretty bad offender when it comes to tearing, some even people experience stuttering and tearing with vanilla vsync.

Thanks.

I think its pretty much what Doom-user said, I think I first heard of it when Rage came out.

Either way, I don't think its particularly useful!?