I'm the proud new owner of an HP g4-1315dx powered by an A6-3420m APU. It came with a single so-dimm of Hynix DDR3 1600, even though the 3420m's memory controller only supports 1333. I've looked around, but can't seem to find the answers to a few question before I decide what RAM I should buy to upgrade it. I know going dual channel will help framerates with the GPU, but I have some questions on quantity and speeds.
Question 1: Should I get an 8gb (2x4gb) kit? will the extra memory do anything for me since the GPU uses system memory?
Question 2: Should I get a CAS 9 1600 kit, as it should default to CAS 7 1333? I can't find a CAS 7 1333 kit without heatspreaders, or should I just stick with a CAS 9 1333 kit?