I work for a Video Fruit Machine Company. I perform "Autoruns" which verify that a game does pay out what it should over the course of 2Million+ games.

While not running google chrome at the same time as my autorun program I get about 1000 games every ten seconds.

While running google chrome at the same time I get 1000+ games every second!

That is a tenfold (approx) increase in speed.... What is going on?

It's not a problem as such, just my curiosity needs satisfying.....:)

I remember reading about similar things a few times and iirc the reason given was that the Flash inside the browser calls a Windows function( timeBeginPeriod(1) ) that changes global timer settings and influences other programs.

I remember reading about similar things a few times and iirc the reason given was that the Flash inside the browser calls a Windows function( timeBeginPeriod(1) ) that changes global timer settings and influences other programs.

That would be my guess too. Maybe you have a Sleep(1) call in your code somewhere. That can sleep for significantly more than 1ms if you haven't done that.

Chrome raises the timer frequency to 1000 Hz, which it really shouldn't do.

Check out Bruce Dawson's blog for more info on the subject: http://randomascii.wordpress.com/2013/07/08/windows-timer-resolution-megawatts-wasted/#more-1285