Zalman CNPS9900 MAX
 

Zalman and its unique fin-ring type heatsinks ruled the roost once upon a time, but things changed with the advent of tower-type coolers. Zalman continued to innovate with a redesigned CNPS9900 MAX, even after going tower-design with the CNPS 10 series. Exactly what made Zalman go back to its traditional design?

http://www.techpowerup.com/reviews/Zalman/CNPS9900_MAX