Vsync fps issues

[cheti]

Hey, so recently i noticed an anomaly with fps and vsync.

Without vsync - fps 70-90
With vsync - fps 50-60

If fps without vsync is 60+ at all times, then why isnt fps at 60 at all times with vsync ?

This is in dota 2, bf3, cs:go etc (the fps scaling varies from game to game tho).

FX-8120 @4.0ghz
GTX 560
8gb of ram
Corsair force gt 90gb


Any ideas ?

 

[blazorthon]

That's simply how V-Sync works. For example, FPS is not constant within a second. If a frame is not delivered within something like a 16.7ms span of time (60FPS is having a frame almost exactly every 16.7ms), that refresh is ignored and during the time between the last frame rendered and the next frame rendered, there is a point where you get 30FPS. That's probably the problem that you're experiencing, if not something similar.

 

[cheti]

wait, so if i drop a frame i get 30fps for an amount of time and thats why i also get laggi/spikyness gameplay ?

 

[blazorthon]

That does seem perfectly consistent with my understanding of the topic, so I'd say yes.