How exactly do Frames-Per-Second work?

PTNLemay

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Sep 24, 2011
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I remember hearing somewhere that a screen's given frequency (in Hertz) is directly related to FPS, and that it's a fixed number. From what I understood (and I may be wrong here), the screen's frequency stays the same and the computer needs to bend it's data feed to work with it. This would mean for example that if a game was running at 30 FPS, the computer would send each frame twice, so that the screen would get a neat total of 60 frames each second. For a game at 20 FPS, the computer would send each frame 3 times, for 15 FPS, each frame is sent 4 times, etc.

My confusion (and the reason I doubt the above assessment is true) comes from the fact that a lot of benchmarks seem to be given in FPS that aren't a factor of 60. How then would a game that's running at 26 FPS send it's data to the monitor? My friend tells me that it just picks random frames and only doubles the ones it neads to come up to the nearest factor of 60. This (he claims) is why you can sometimes feel something is subtly wrong with an image, but can't quite put your finger on it. Your eye can just catch the frames that are lagging, and they stand out in comparison to the frames that have normal frequency.

Can someone please give me a more thorough explanation to how FPS and screen frequencies work in relation to one another, or at least link me to a webpage/video that offers a nice explanation of it?
 
benchmarks use fps since it allows comparisons in processing power. remember you are comparing the system and not the monitor.

it doesnt matter if you are getting 2fps or 180fps, the monitor still chuggs along at 60hz.

one hertz = one cycle per second therefore 60hz = 60 cycles per second.
one fps = one frame per second. therefore 60fps = 60 frames per second.

see the correlation here? sure input lag and other factors do apply but in general 60fps = 60hz. anything greater than 60fps is irrelevent unless you have a 120hz tn panel monitor.

i believe what you said above is true. if the fps is less than the hz then the frames get processed by the gpu so that it fits into this standard 60hz. this would equate to duplicating frames. if the fps is higher then this would equate to deleting frames.

for uneven frame rates i'm sure it doesnt choose at random. most likely it trims them in some sort of pattern.

some games cap your framerate at 60 so even if your system is capable of 150 or higher framerate you will still only see 59/60 fps.