If I install an additional RAM bar in my laptop, will it be displayed or was it available at the time of purchase?
For example, if you upgrade your 4GB with another 4GB (assuming they match), then Windows will simply show 8GB of RAM. Hope that answers your question.
If you remove the old one and the new one, then the new one will be displayed.
If you open the new one and leave the old one in, then the old one will be displayed.
If you both open, both are displayed. However, only the speed of the slowest module is used.
With the tool CPU-Z you can see under Memory and SPD how many Ram Slots are available and where a Ram Module and which Ram is in it.
https://www.cpuid.com/softwares/cpu-z.html
