High performance RAM is no different than normal RAM; Only this kind of RAM has ability to be overclocked (hence 'high performance') more compared to normal RAM. Normal RAM can't be overclocked, or maybe only a slightly bit overclockable.
But in terms of working condition and performance, the things are no different.
Please bear in mind that if you mix HP-RAM with normal RAM, the overall speed will run on the slowest one (normal RAM). Also, if you mix, please get same brand, same spec, same type, to make sure you get higher chance of them working together.