On Windows sleep / timer resolution is 16ms by default however. That can be changed systemwide with NtSetTimerResolution() / winmm.timeBeginPeriod and AFAIK (didn't test that myself) 0.5ms is the best supported resolution (only available through NtSetTimerResolution). So it is interesting what the game does exactly, which sort of delays or waits affect the performance and how that works on Windows.
Just making sleep precision as good as possible might instead negatively affact the performance in some other games.