Not sure...

It causes a delay in QB, but I'm not sure if it prevents CPU usage.
I ran a test in FB (see source below), and while it limits the frame rate to just under 60FPS, it does not lessen the CPU usage.
If all the QB programs used this Wait command consistently, you could add something to QB64 to make it Sleep there, but I know many QB programs don't use this Wait delay at all. It's something to consider.



Dim As Integer fc
Dim As Double t

Screenres 800, 600, 32

t = Timer
Do
fc += 1
Screenlock
Circle (Rnd * 800, Rnd * 600), Rnd * 300, Rgb(Rnd * 256, Rnd * 256, Rnd * 256),,,, F
'Screensync
Wait &H3DA, 8
Locate 1: Print fc / (Timer - t)
Screenunlock
Loop Until Inkey = Chr(27)