I would like to know the differences between these two concepts. And on the other hand, I would also like to know which protocol is used to create one or the other. RAMdisk I think is a disk that is loaded in RAM, and the RAMcache, according to this article, seems to be an intermediary between the disk and the applications.
Then, I have seen that RAMdisk can be activated from the motherboard BIOS, if it offers that option. What is the associated software to perform such action, is it in the BIOS itself or another chip?
Yes, our RAM Disk is something that's called a software RAM disk. It allocates a block of RAM and treats as if the memory were a disk drive. In other words, it creates a super-fast disk residing in RAM, which is volatile in nature. Anything written to it completely disappears on shutdown (unless the user chooses otherwise), so it's usually used for temporary data like caches and temporary files. The user has to explicitly use the disk or setup his/her programs to do so, as just the fact of having a RAM disk installed doesn't speed things up.
The RAM disk options in BIOS appear to be the same as a software RAM disk, i.e. treat some of your RAM as a disk, just like our product does.
RAM Cache on the other hand, indeed seems to be an intermediary, caching bits and pieces in RAM automatically. I am not so sure how exactly it works and whether it provides a performance boost, but I suppose it's the simplest option for regular users.