The DELL XPS 12 supports a 1,600MHz processor memory clock speed which is faster than most 2 in 1 laptops that are a comparable age to it. Most comparable spec portable PCs that have been on the market for a similar time to it support a 133MHz processor memory clock speed. This portable PC also supports 1 and 333MHz processor memory clock speeds.
A 1,600MHz processor memory clock speed is in fact the best supported memory clock speeds supported by processor across all laptops of a comparable age and type to the XPS 12.
The worst supported memory clock speeds supported by processor amongst similar types of portable PC is 133MHz.