8 GB DDR3 RAM v.s. 4 x 2048 MB DDRII PC667 RAM
What is the main difference between 8 and "4 x 2048"
They both equal the same amount of RAM right?
And what is DDR3 and DDRII?
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There are a few things:
They're each 8GB of memory -- one is of DDR3 and one is of DDRII.
DDR3 is generally preferred over DDRII. This page talks about the difference between the two.