The DELL Inspiron 15 3521 supports a faster memory clock speeds supported by processor than most medium processor core notebook PCs that are a comparable age to it. This portable PC supports a 1,600MHz processor memory clock speed, whereas most notebook PCs that were released more than two years ago support a 133MHz processor memory clock speed. In addition, this DELL laptop supports 1 and 333MHz processor memory clock speeds.
This notebook PC's memory clock speeds supported by processor (1,600MHz) is in fact the best supported memory clock speeds supported by processor amongst all similar spec portable PCs that have been available for around the same time as the Inspiron 15 3521.
The worst supported memory clock speeds supported by processor across similar types of notebook PC is 133MHz.