Can I add another pair of G.Skill F3 12800CL10-8GB on top of this?

[appplejack007]

I have a pair of:

G.Skill F3 12800CL10-8GB (2X8GB) on Asus Maximus Hero VII.
I want to add 2 more of the same rams but the trouble is that I cannot find the exact same ram.
The closest I could find was: G.SKILL F3-12800CL10S-8GBXL

http://https://www.amazon.ca/G-SKILL-F3-12800CL10S-8GBXL-Ripjaws-240-Pin-DDR3-1600MHz/dp/B0065HOT2W/ref=sr_1_fkmr3_1?ie=UTF8&qid=1506706646&sr=8-1-fkmr3&keywords=g+skill+f3+12800+cl+10

If I buy two of this, what kind of trouble can I expect? Because I know that the best practice would be to buy 32gb of (4X8gb) all at the same time instead of this but.

 

[brispuss]

The best way would be to get a quad/dual channel 4 x 8 GB kit where the four modules have been tested for and guaranteed to be compatible with each other.

Trying to use individual modules and/or modules from different kits at the same time can lead to inter-module incompatibility issues, and is not really a recommended procedure. If trying to go this way, then be prepared to try several other kits/modules until an inter-module compatible combination is found.