Hey, welcome to the site. Glad you're having fun on the ol' Xbox, Left4Dead is tons of fun!

Yes, the only HDDs available for the slim Xbox 360 is 250gb and 4gb. It is removable, as demonstrated here

YouTube - Xbox 360 Slim: How to Remove Hard Drive

You can pick up a 250gb HDD here, if you wish 250GB Hard Disk Drive for Slim Console (Xbox 360): Amazon.co.uk: PC & Video Games. You'll need a transfer cable to transfer your data over to the new HDD which can be found here Hard Drive Transfer Kit (Xbox 360): Amazon.co.uk: PC & Video Games (Pricey I know)

EDIT: By the looks of it you can't use the transfer cable from slim HDD to slim HDD, only between the old HDD to new ones. Will update if I do come across one

Alternatively, you could use a memory stick to act as a storage device. You'll need to set it up to work via the Xbox. 16gb is the largest external HDD/Memory stick size that is supported (larger ones can be used but only 16gb can be used - though you can use 2 x 16gb External HDD's/Memory Sticks to get 32gb, if you have USB space). You can also use it to transfer data to separate HDD, handy! You can find a cheap memory stick here SanDisk Cruzer Blade 16GB USB Memory: Amazon.co.uk: Computers & Accessories


Happy gaming

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