Start and end switches

[carmaa]

I'd like to be "end" a value that I can configure (as I stated at the beginning it IS possible to access RAM over 4 GiB) - set default 4 GiB but let the user override when he wants to.

When trying "Screenlock" it would be great if the user could define a start address. In my findings the relevant code is always near the end of the available memory range - if the target is a system with 16 or more GiB of RAM it's a waste of time to start at 1 MiB - but that's just an idea.