The Intel Core i7 4500U is an, ULV (Ultra Low Voltage) processor, based on the Haswell architecture. It was released in the second quarter of 2013 and includes two cores, each of which is clocked at 1.8GHz but they dramatically increase their speed, with Turbo Boost, to 2.7GHz, if both cores are overclocked. The 4500U can handle up to four threads, due to Hyperthreading, and has a 4MB L3 cache. Also, the 4500U has an integrated HD Graphics 4400 with a base speed of 200MHz, and a max speed of 1100MHz with Turbo Boost. All this makes the 4500U a great choice for ultrabooks, and is able to perfectly handle office and multimedia tasks.
Note: information origined from http://cpuboss.com/