Parts needed. Power supply and USB board.

[JAZZCNC]

Ok thats confirms most of what I understood. Just a bit confused about BOB. https://onedrive.live.com/view.aspx?...PSeNu5hZHOhv5k seems to show a BOB but also a controller conmbined ...
.....but is that what a BOB is and I have a really cheap one on the chinese CNC box??

Ok this a common misunderstanding new comers make when they see boards with USB connections.? . . . Clive is correct that's just a BOB which draws it's power from the USB, it doesn't take signals from the USB port only the 5V it needs to run.
This in it's self is not a good thing either as the USB port is unreliable at provideing a stable power source due to way PC's manage energy so turn off the USB port while in-active and because the board is only drawing power not signals the PC thinks no activity is happening so powers down the USB. If using USB you must change the PC's energy saving mode.
BOB's and inparticular motion control cards are best powered from a separate power source. Some BOB's can be powered by higher voltage source than 5V and will take there power from the PSU driving the drivers.

Also not all BOB's require power.? Those that do usually need it to power the opto isolators that protect the input and outputs or for powering on board relays etc.
Yours will either take it's power from the 24V PSU or not have any at all in which case it's a basic cheap n nasty BOB.!!

This one you highlighted before is a BOB and motion controller combined. http://www.shop.cncdrive.com/index.php?productID=367