wasted devoted most of the week to playing Dead Rising on the 360, which in our opinion is the best game on Xbox 360, hands down. However, some users have been saying that the demo has been frying their Xbox 360 because it uses 2 or 3 of the system's cores simultaneously, which will really tax the cooling system.
We haven't had any problems on our systems, but on Kotaku's informal poll, 14.1% answered "Yes" to the question of Dead Rising freezing their 360s. That's a pretty high percentage, even accounting for the vote-yes-for-fun factor.
Dead Rising Killing Xbox 360s? [Kotaku]