Sul Forum US di Wolfenstein c'è la risposta alla tua domanda e te la riporto qui sotto. "Which disc do I need to install on my Xbox 360? Wolfenstein's first disc must be installed to the Xbox 360 or an external USB flash drive with at least 8 GB of available 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. Note: Discs 2-4 cannot be installed to the Xbox 360 HDD. These discs should be used on your Xbox 360 as prompted by the on-screen directions."