I am interested in setting up a new rig and I wanted to go for the i7-2700k but on Intel's official page it says that the CPU supports DDR3-1066/1333 memory types. I wanted to go for 1600MHz but now I am not sure if my ram will essentially be 'downgraded' to run as 1333MHz? If that is the case - is there even a point in going for 1600 on a platform with i7-2700k?
With the 2nd generation Intel® Core™ processors like the Intel Core i7-2700K support only DDR 3 1066/1333. However you can use DDR 3 1600 but in most cases you are going to have to set it to that speed in the Bios on the board since it is technically overclocking. I haven't heard of anyone running into problems with DDR 3 1600 memory but I have heard of cases where people have problems based on the voltage. Just make sure that the memory that you use is 1.5v ±5% (1.425v to 1.575v) and nothing higher.