Most likely (although you haven't provided any information, so we can't be sure), your machine is using the 8254 time counter.
Earlier it would have been using TSC for timekeeping, but TSC is so unreliable on so many machines and it's more or less impossible to know when it can be trusted, so TSC is not used anymore. In reality, what matters is that the timecounters are MP safe and support wider range of hardware. The code might be slower. Or might be faster when you have the right hardware. //art
