As a result neither the Arcade nor the Elite are currently in production. The major difference between the Elite and the Arcade is the presence of a Hard drive. While the Arcade does have a small amount of on board memory, it isn't much. Additionally, the Elite comes with a Headset and Ethernet cable.
When you press the power button to start your Xbox 360 console, the PSU fan starts. Typically, the PSU fan makes a "whirring" noise. When your Xbox 360 console is in Sleep mode or when the console is disconnected from the PSU, the fan does not operate. The speed of the fan increases or decreases when the temperature of the PSU changes.
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