increase the CPU frequency in RB-951ui router board

Hello for all Mikrotik people there…!
so i have two question :
1- what is the benefit of this increasing the CPU freq feature in router..? is that mean that the router CPU will became better in its performance..?
2-what is the different between this two type of booting protocol -(see the attached file)- bootp and dhcp
bootp.PNG
fre-1.PNG