"largest and most ambitious" GTA ever will require mandatory installs.
The Xbox 360 comes in two discs, as opposed to PS3's single Blu-ray, and will need either HDD or USB memory. The first Xbox 360 disc is for installation only, the second is to play the game.
If using an external USB drive then Rockstar advise a 16GB drive with at least 15mb/s read speed, and of course formatted for use with the Xbox 360 console.
"Grand Theft Auto V is the largest and most ambitious game we have yet created, and takes full advantage of every ounce of processing power available in the current generation of consoles," answered Rockstar Games. "In order to provide the best possible experience for such a massive and detailed world, the game will have installation requirements on both Xbox 360 and PlayStation®3 systems."
Once installed on Xbox 360 with disc one there will be no need to swap discs, even when going online.
"This initial install will require an Xbox 360 Hard Drive or an external 16GB USB flash drive with at least 8 GB of free space. If using a USB flash drive it must be at least USB 2.0 with a minimum 15mb/s read speed and formatted for Xbox 360 use. A new USB flash drive is recommended to ensure optimum performance."
"For PlayStation®3, the game ships on one disc and will install content as soon as you insert the game. The install is roughly 8GB, and players will be able to play as soon as the install is complete."
Grand Theft Auto V releases on Xbox 360 and PS3 September 17th. Better spruce up that HDD space.