Both frequencies are being correctly reported, because the Intel D850MV motherboard does not support a 533MHz Front Side Bus (FSB) speed.
The so-called 533MHz FSB speed of motherboards that support it is only the base FSB of 133MHz multiplied by 4 to express the effective FSB speed of the RAM, which is not a frequency. It is the effective speed (frequency) of the RAM using DDR RAM and DDR RAM operating in dual-channel mode. The RAM would be running at an effective speed/frequency of 133 X 2 = 266MHz using Double-Data-Rate (DDR) RAM, which functions at double the data rate of the FSB.
