The HDD has faster access times than the USB port allows, while you got a USB 3.0 drive, the USB ports on the 360 are only USB 2.0 ports. So games like BF4 that rely heavily on streaming data from storage require the speed only the internal HDD provides.
Flash memory is not considered a hard drive. If a game such as BF4 requires a hard drive, then you must have an official Microsoft hard drive to play the game. They are available for the slim xbox in 250gb and 320gb sizes.
Also, the MS hard drives have other system files on them required in order to run certain things. Flash drives won't have that.
Thank for your initial answer, which of course raises more questions. With the Xbox 360 I have (not a slim) and its limited memory can I expand its memory by adding an internal HD somehow, is there other options? Or will I never get to play games like BF4 that require lots of memory
Bazajaytee - be aware that both of those drives that you linked to are being sold by 3rd party vendors and are likely knock-off hard drives. Drives not sold by Microsoft or Amazon themselves are usually generic hard drives slapped into a casing to make them fit an Xbox. They have a history of failure as well as lacking software partitions that Only the official hard drives will have. These things can lead to more problems down the road and should be avoided. Hard drives should always be purchased from reputable retailers.
SLiKer11 - For Battlefield 4, you'll need an official Xbox 360 HDD which can be purchased from trusted retailers. It's really easy to install, too. For future reference when using a USB drive on your Xbox 360 console, check out the requirements here.Hit us back if you have any other questions!
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