how long it takes since play button till playback starts??

Trying to work live with cubase,
and to figure out how long it takes from the time i hit the play button,
till the playback starts, so i can put the markers according to that…
is it the same on all systems or it depends on the computer/operating system/ size of file etc…

using windows 7 , 32 bit with m-audio fast track pro.

It depends on the output latency of the system. Make sure you have the correct driver selected in cubase and the latency/buffers optimised for your system

To add to that: it also depends on the internal latency of the plugins you use in the project (and the number of those added up). So it’s different for different projects.