An odomoeter for CPUs

You know when it´s time to get a new car. Your odometer is far into six digits, perhaps the engine is burning lots of oil, or the transmission is growling. Fixing all that might well cost quite a bit more than your ancient vehicle is worth. But what about your microprocessor? Unlike automobiles, microprocessors don´t have convenient little gauges that reflect how much wear and tear they´ve endured. And wear they do-though you´ll probably never notice it. The degradation of their transistors over time leads slowly but surely to decreased switching speeds, and it can even result in outright circuit failures.