Although gamers are free to try standing it up on its side, Xbox One is only designed to be laid flat on its bottom, Microsoft has reconfirmed. Microsoft first indicated the system was meant to be laid horizontally earlier this year, explaining to IGN that "the airflow and venting system was optimized for this horizontal orientation."
Following up on this, Microsoft's director of product planning for Xbox, Albert Penello, told GameSpot, "We don't support vertical orientation; do it at your own risk." He expounded on this, saying the risk comes not from ventilation, but the disc drive. "t wouldn't be a cooling problem, we just didn't design the drive for vertical. Because it's a slot loading drive, we just didn't design it for both," he explained.
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Not good news for those with space issues.