How to detect if RDTSC returns a constant rate counter value?

Question

It seems most newer CPUs from both AMD and Intel implement rdtsc as a constant rate counter, avoiding the issues caused by frequency changing as a result of things like Turb

Answer 1

just use CPUID to detect the generation of the CPU, see if its using constant counters. I'd however, suggest using a profiling API instead though, something like AMD's codeanalyst sdk would do well