regarding the ITB, if i did not install the driver, is it possible that its not ON?

There are two options one is Balanced and another one is Power Saver and another one is High Performance

Power Saver usually you use it when you r using battering only and not plugged in and this setting will reduce processor’s clock speed and display brightness with the intention of increasing battery life

Balanced option is where the system will set the clock speed based on requirement by the required running application, so it will set up the clock speed according to required applications only. (I will suggest this so it is balance between high and low).

High Performance is where the settings will set to full clock speed (maximum) based on the required running programs and this setting will use full power, if you use this when  not plugged in, then your battery will be empty very fast.
**What is Clock Speed?  -> The CPU requires a fixed number of clock ticks (or clock cycles) to execute each instruction. The faster the clock, the more instructions the CPU can execute per second. Clock speeds are expressed in megahertz (MHz) or gigahertz ((GHz)

hi price j, i downgrade back to win 8.1, i have checked my bios version is still 131
Am i able upgrade to 151?
What is the difference between two version

First Z5 customer with Windows 10!