360 Slim hard drive

the slim hard drive cannot work with the older gen 'fat' 360s that had clip on drives, the slim drive only fits inside slim model 360 consoles.

For Original Xbox games to be playable on an Xbox 360, it needs to be an official Microsoft Hard Drive.

However, there is no official 120GB hard drive for the Slim, only 250GB and 320GB.

There is a 120GB for the original-style Xbox 360 and the later Elite, but not Slim.

If you are using a Slim, the hard drive itself will be the problem and you will need an official one.

Get the slim it's better, however getting your old hard drive memorie to the new slim hard drive will require that you buy an Xbox 360 Hard Drive Transfer Cable to make it easy.

It is the slim 4gb Xbox 360. The hard drive is a Go! Data 80gb external hard drive. It did work with the same slim xbox previously but now it doesn't.

To play Original Xbox games, you need an official Microsoft hard drive.

There is no official 120GB hard drive for the Slim. For the Slim, the hard drives are 250GB and 320GB (and one with 4GB internal flash memory); there is a 120GB hard drive for the first iteration Xbox 360 and later Elite console.

So if you're sure yours is the Slim variant, the hard drive itself will be the problem.