Brand new computer

Hi, I just bought a brand new computer,

and I opted for a much betetr memory speed, I suaully gifure that ram was a bottleneck in the computers speed cause it ran so much slower than the MB and CPU... however, increasing the speed on my ram did not seem to provide a very noticeable difference in my overall computer speed... why is this?

DETAILS:

CPU - INTEL E6850 (3 ghz, 4 mb l2 chache)
MB - Asus - 1333 mhz
RAM - ???? (brand unknown) 1033 mhz