Why does VSync hurt my framerate so badly?

Something I've noticed recently while playing the original FEAR...

When playing with VSync turned off, I get anywhere from 30-110 FPS on high settings at 1152 × 864 (I only have a 60Hz LCD though). The value it hovers around for most of the time is 55-70FPS.

So when I turn VSync ON, I'd expect to get from 30-60FPS, getting 55-60FPS most of the time... But it hovers around 40FPS unless I'm looking at a wall or there's lots of things happening oncscreen, and I don't understand why...

Anyone care to shed some light on the matter? I don't like tearing much, but it's a non-issue compared with a 30-40% cut in framerate.

 

Theoretically you should see roughly 60Hz which is your maximum supported LCD refresh rate, unless your monitor is already starting to weaken which I doubt is possible.

FEAR is somewhat old and newer graphics drivers may have problems bringing out maximum performance out of the game.

 

Try Nvidia official 182.XX drivers.

 

Do they support overclocking? I OC for oblivion and dark messiah...

I guess I'm just wondering why it seems to lower my framerate like it's putting a heavier load on the GPU, when it should just be putting a framerate ceiling at 60FPS.

My LCD's fine, it displays 60FPS no probs.

 

i'm about 90% sure the following is correct:

if your framerate > refresh rate, vsync caps the framerate to your refresh rate

if your framerate > 1/2 your refresh rate and but < your refresh rate, vsync caps your framerate at the difference between your refresh rate and 1/2 your refresh rate... in this case, 45fps.

so with vsync enabled, you are either at 60fps, 45fps, 30fps, or 15fps (with a 60hz monitor.) there are no "transitions" between these values... if your gpu goes from being able to render 65fps to 58fps, you see that as 60fps to 45fps with no transition.

the tradeoff is that you eliminate tearing artifacts.

 

+5 to the man above me.

 

I love vsync. I always use it.

 

This is somewhat wrong.

Lets go with a 60Hz monitor. With vsync on, it goes from 60FPS strait to 30FPS. There is no in between. If your FPS display is showing something in between, the monitor is actually only running 30FPS, and not what the FPS graph is telling you. FPS graphs display the framerate of the DirectX or OpenGL application they are tied to, not what the monitor is receiving.

I would never recommend using Vsync unless you average over 100FPS in a game merely because of this. There's also a huge delay vsync causes that makes playing FPS games with it on unbearable. I personally find the screen "tearing" issue not really all that distracting, I hardly ever notice it, and even when I do it doesn't effect the experience. The tradeoff between some minor graphical artifacts only noticed when moving the view very fast vs HUGE framerate fluctuations and mouse lag isn't worth it.

 

I like VSync on most of my games but for Source games I get a mouse lag. It's not a major lag or anything but it seems like the response time from when I move my mouse to when my guy moves on the screen has like a .005 second delay, which is just enough to screw me up

On a side note with that though a friend of mine had it too, but he didn't notice it until I said something about it. So next time you guys are playing a source game (Portal, CSS, Half Life 2) look really closely at the response time in your mouse and lemme know if you get it too.

As far as other games go though (COD4, CODW@W) I don't get the lag and Vsync is great. Anyone else have this problem?

 

^ Yep. It wasn't a problem for me until someone told me to use Vsync to cap my frame rate, since I was overkilling Source with a whoping 200 FPS.

Ohhhh what a bad idea that was. HUGE mouse lag. Never going to touch Vsync again. Although I did find the fps_max command in console and that worked like a charm.

 

Odd, CS: S is perfectly fine for me with vsync. But im using a wacom tablet with the wireless mouse thingy.

 

I liked Vsync while playing games.

 

Hmmm... At some stage I'll test all my games with and without VSync, and I'll post anything interesting back here...

Back to the oldschool, Summoner and Soulbringer had TERRIBLE mouse lag, even on a modern machine... If it was VSync, there will be blood =/