Does dual booting split RAM between the two systems?

Others have already answered correctly that no, the RAM would not be split in this case, but I want to add an explanation of why that is the case.

I find a helpful analogy for the workings of a computer is a kitchen. The RAM is the counter space. It's a close-at-hand space for temporarily storing things you are working with. Like a kitchen counter getting cleaned when finished cooking, the RAM is wiped when the computer is powered off. The hard disk is the fridge and pantry, long-term, less easily accessed storage. The data is the ingredients, and programs are recipes. The chef is the operating system.

You are the owner of the house, and currently employ an English chef (Windows). You want to try some recipes from cookbooks that are written in French, but you can't find suitable translations. So you want to hire a chef who speaks French (Linux).

Since the chefs each have their own set of cookbooks and ingredients, they'll each need their own space in the pantry (hard disk) for as long as you employ them. Whether they need to split the counter space (RAM) depends on if they work at the same time. If only one chef is working at a time, they will have exclusive use of all the counter space. The other chef's things are off the counter and in storage. If however, you run two operating systems simultaneously, like telling the chefs to work together, one as Head Chef (host) and one as Sous Chef (virtual), then they will need to split everything. They will have to take turns with the appliances (CPU, GPU, etc) and will need to mark out separate working spaces on the counter to put their cookbooks and ingredients while working.

For dual booting, no... You'll either have one or the other running at one time.

If you want to have both running at once, then you could use a hypervisor.

You might be interested in one of the following:

• VirtualBox - run Windows or Linux natively, and put the other in a VM - type 2 / hosted
• ESXi - run both Windows and Linux in a VM - type 1 / native

No, they will get 8 GB (provided they are the x64 version of the OS).

When dual booting, only one OS is running at a time.

You do need to give them both hard disk space when you are installing them, but they both get full access to the system RAM when they are booted up.