Windows timers generally run off the hardware timer, which has a resolution of 10 - 15ms (depending on the hardware, most run at 15.6ms intervals) so when you ask for a lower interval, you get an accuracy of 10ms in teh timer value, but a resolution of 15ms in the timer interval.
There is an article here which may help, but you have some work to do!
http://msdn.microsoft.com/en-us/magazine/cc163996.aspx[
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