[SOLVED] How does upgrading ram actually works?

[Noor_awsome]

So I decided to add more ram to my gaming/work pc. The motherboard I use is this one https://www.gigabyte.com/Motherboard/B360M-DS3H-rev-10#kf that can support up to DDR4-2666. I currently have 2x 4 Gb DDR4-2400 CL5 Memory G.Skill ram sticks installed summing up to 8gb of ram. I decided I should upgrading by purchasing 16 gb of DDR4-2666 ram sticks.

However what does upgrading ram means?
- Replacing old ram sticks (taking them out) and replacing them with the new purchased ram sticks. In my case installing 16 gb of DDR4-2666 ram to my system.

or

- Adding 16gb of DDR4-2666 ram (noticing my motherboard has 4 ram slots) with my 8 gb DDR4-2400 ram. Meaning by adding 16 gb I will have 24 gb to my system. I would purchase ram sticks from the same brand (ex: G.skill Ripjaws V series 16 gb) . Would the varying speeds of ram work?

 

[MeanMachine41]

It is never a good idea to mix RAM kits due to Latency differences so your first choice is best. Even an exact brand and RAM spec can cause issues.
Your choice of RAM should be a single kit (2x8) 16GB at 2666MHz and chosen from the MB QVL to ensure they have been tested and known to work.
Some do try mixing RAM and sometimes they do work however only at the slowest rated frequency.