[konzy]

Hello everyone.

I´ve been using a recently bought Macbook with an Apple Cinema Display as an external monitor. I use it in closed-lid mode, along with an external keyboard and mouse.

I never had problems with this until 2 days ago, when it suddenly shut down. I grabbed the MB and it seemed really hot. I unplugged everything, turned on the MB again and plugged everything back in and after a few minutes, it shut down again.
So I thought it definitely overheated.

I stopped working with the cinema display and today I plugged everything again and after an hour or so, shut down again and the MB was really hot...again.

Apple says the closed-lid mode is totally safe. But i´ve been reading some stuff in other forums and this doesn´t seem to be the case because a lot of people are complaining about it.

Does anyone care to comment?

I´m going to try to work with the lid open (but without mirroring) and if that doesn´t do it, I was thinking of buying those suppports that held up high the computers. But I can´t help to feel disappointed if after all, Apple doesn´t know what it´s talking about...

Thanks for your time!!

[Simon]

Closed-lid mode is safe. Apple's portables are designed to be used that way and Apple explicitly endorses closed-lid mode. If your MB is indeed overheating in closed-lid mode it's faulty and Apple will fix/replace it under warranty.

The first step however is to find out what is causing your shutdowns. My guess would be a broken fan or bad temp sensor.

Run Apple Hardware Test (it's on the DVD that came with your MB) and see if you get any error codes. A broken fan or temp sensor should show up there. A second step will be to get smcFanControl and see what kind of temperatures you reach under different types of use and how your fan reacts. Tell us what you find out.

[shrugs*]

My MB spends ~15hrs clamshell and ~5hrs free-range everyday: no overheating problems and I do CPU-intensive work using a 7200RPM hard drive. Maybe check the logs via console for more evidence as to what's going on.