I live in the bahamas and it's pretty hot all year round here. The room that I have my ps3 in is pretty small, has 1 window, and one door. I usually have the window closed. My ps3 pushes out quite a bit of heat when the window is closed, and it does make noise but not much. But I've had people walk in the room and noticed that just walking through the open door feels like the temp has raised by 8 degrees or so. My room's bigger, when my ps3 was in there it used to be quiter and didn't push out as much heat, I would always have a fan on, my door would be closed, and the windows would be opened. Mine is a 80GB BTW...
However my bro's 60GB runs load after being on for under 20 mins. And pushes out heat like crazy, even if he's in his living room, 2 windows open, and nothing blocking the way from the kitchen, just a huge walkway. I just assumed all launch 60's were loud, but on the internet I see that they aren't much different from the 80's in the motorstorm bundle [the one that I have], unless you cound the EE chip.
4 ≈ One
