I'm about to buy 1GB ram from Crucial. http://www.crucial.com/eu/store/lis...k+G4+1.67GHz+(15-inch+Display)+DDR2&submit=Go They offer two kinds of 1GB ram sticks. A CL 4 and a CL 5. My PB 15" DL is equipped with CL 4 ram right? So I should get one of those?