I have a Gateway FX 6800-01e with 3Gig DDR3 ram. I was hoping to add some more since I have FSX. I see that DDR3 comes in 1333 and 1600 clock speeds . First, how do I find out what clock speed I currently have, and can I mix the 2 together or do the modules all have to be the same? Thanks. Regards, Tom

You will be best off to purchase a new matched set of RAM 3X2GB (unless you know exactly what Gateway has installed). If you are planning on oveclocking at all go with a 1600mhz kit.