"I know this is an old post but online there are different answers to this question. I am adding this in case someone needs the ultimate info:
The asus x551ca-sx024h PCB rev 2.2 doesn't have any additional slot, see the pictures, in the last one you can see that the slot is empty and the RAM is soldered directly in the PCB"
the RAM limit on your notebook is 8GB so, you can upgrade your RAM, its really simple to change it. if you haven't bought the RAM the check this crucial link http://www.crucial.com/usa/en/compatible...
