PR4100 RAM requirements for paired Modules

Legacy Products My Cloud OS 3
1

Hello,
Can someone confirm whether paired RAM modules are required for the PR4100?
The manual suggest so, but good to know if this is really the case.
i.e. if I obtain a single 8GB module, can I use it on its own, or in combination withe one of the modules already installed?

2

They need to be paired.

3

I made a post as well can someone see if this memory will work Memory compatibility check