RonRave :
You should be able to! You'll want to check and see if you have an open slot to add 4 GB or if you need to buy a single stick of 8 GB!
I do not buy it yet, I need to know for sure before I buy it.
this is 3 model I am looking for
20FQ003KUS
20FQ003NUS
20DL0036US
I do some research, seem like Think pad Yoga X1 memory has been soldered on board no upgrade slot. that what I found on youtube