The amount of space one has on a hdd has no real relation to the amount of partitions one can make. So yes you can use 2 partitions or even one.
Yes there are tutorials for installing to a hdd and or usbIs there a tutorial for this, or do u guys say its better to use de pendrive install.. if so is it possible to save changes i made to BT4 to that pendrive?
You need to use the search function.



