JingleCoffey wrote:
I had no idea what it did tbh, well I know it syncs vertically but that's about it.
I read a readers letter saying he was getting shit FPS in a game, they told him to disable Vsync ALWAYS because it gave a massive hit in performance.
So that kinda scared me off of ever using it.
I noticed in the menu that I got some lines appearing sideways accross the monitor, but put that down to it being a cheap monitor with crap response time.
To Vsync or not Vsync.. that is the question...
Ok - rendering takes place to an offscreen buffer always, of which there may be multiple. If you have Vsync on, then when the monitor scan line is in the vertical blank (ie.e off the bottom & looping back to the top in an old cathode ray monitor, and LCDs still use the same format for signal timing), that is when the current display is changed to the latest rendered frame. If VSync is off, it shows the latest frame as soon as it is ready, no matter where the current scanline is on the display.
So - if something is moving fast, and you monitor is refreshing at 60Hz, but running flat out your card is chucking out 120 FPS, then you will see 'tears' on the moving things. But you get a big number in the FPS count, which is used for epeen rating.
Difference it makes? Bugger all. So what if the top half of your screen is showing something 20ms in advance of the bottom half. Id that really gonna make the blindest bit of difference considering your eyes can only detect motion at around 25-30FPS anyway. 60 feels smoother, but going above that actually detracts from the realism as your eyes expect blurs with fast motion and not static crisp frames (hence why ultra-detail fast stuff looks 'artificial', and we now have a plethora of after effects to try and mimic the blurring our eyes do in the real world.... meh
There is an argument that 10ms updates (100Hz) means things are more responsive in-game. That may have been the case (Quake 2 era), but these days, for the past 10 years any game programmer worth his salt knows to decouple logic from graphics & run at a fixed update (usually 25 or 30Hz, sometimes 50/60 for twitch games), so FPS & gameplay aren't coupled any more, so the argument doesn't wash.
So - VSYNC good if you actually want to play games that look good, don't blow up your PC, and don't make your eyes bleed so much. Golden rule - FPS is NOT a raw measure of performance. Low FPS indictates bad performance, but if you can maintain refresh rate (50Hz+) with VSync, then squeezing any higher gains you no actual performance, just burns up your PC faster and introduces tearing.