They run at 1333.
CPU-Z lists the actual speed.
DDR (double data rate) transfers data on both the rising and falling edge of each clock cycle.
So to get this straight if I had a quad channel version of my memory stick then the actual speed would be around 333MHz? Also what advantage does my memory have over a single channel kit?
2x2GB 1333MHz vs 1x4GB 1333MHz
No, with DDR the actual speed is half of the advertised speed. If 1600 MHz, for example, CPUz would show 800, no matter the number of RAM modules.
Dual channel doubles the bandwidth (data is accessed in parallel mode).