[striker100]

Does using a Powerbook closed attached to a Cinema Display effect the Powerbooks display at all? Can the heat buildup of the Powerbook be detrimental to the Powerbook display?

[H * � �]

Originally posted by striker100:
Does using a Powerbook closed attached to a Cinema Display effect the Powerbooks display at all? Can the heat buildup of the Powerbook be detrimental to the Powerbook display?

I suppose it could, but I've run mine that way continuously for three years with no affect.

[jessejlt]

They're engineered to run with the lid closed. I don't think they vent through the keyboard nearly as much as the iBook's do, so it shouldn't be an issue.

[rag on a muffin]

you didnt mention which powerbook you had, but even if its the 12" which gets incredibly hot, is not and issue, because only the bottom gets hot enough to be dangerous to the display. the very top where the fan is the hottest part, and it is covered by the bottom of the screen when its closed.

[Hanul]

I'm a little bit skeptical with my 12" PB. I always open the lid a bit for better air flow over the palm rest, where the HDD can get hot. When opening the lid *after* setting up the external display the internal one stays turned off.

[Macola]

Originally posted by Hanul:
I'm a little bit skeptical with my 12" PB. I always open the lid a bit for better air flow over the palm rest, where the HDD can get hot. When opening the lid *after* setting up the external display the internal one stays turned off.

Exactly--this is the best way to do it with the rev A 12", mine still gets warm enough. I ran my first TiBook in clamshell mode for 2+ years without the lid cracked open, and the display died. It may have just been a coincidence, but...

[escher]

I just got a 12-inch PowerBook, my first 'Book able to run in clamshell mode. When I run the PB with only the internal LCD, the fan comes on intermittently. But when I run it in clamshell mode, the fan runs all the time, whether the 'Book is actually closed or not. So it would seem that clamshell mode generates more heat.

However, the PowerBooks are specifically designed by Apple to run in clamshell mode. So if you are still within your 1-year warranty, or have AppleCare, I wouldn't hesitate to ask Apple to fix any screen that may have failed due to heat. It's their design after all.

Escher

[Dr.Michael]

Originally posted by escher:
But when I run it in clamshell mode, the fan runs all the time, whether the 'Book is actually closed or not. So it would seem that clamshell mode generates more heat.

That depends also on your external resolution. If you run 1600X1024 the gpu has more load and gets hotter than with the internal 1024X768. So you heat your machine with the cpu, the hd and the gpu. Thats the reason why the fan runs constantly.

And talking about design. I don't think that apple has tested their powerbooks with all possible modes of lid closed operations in all possible climates. So I don't think that the technical possibility to do a lid closed operation does also mean its always safe. But thats only my impression.

Michael

[all2ofme]

I use my 12" with a 20" Cinema display almost exclusively and while the fan does come on far, far less when I'm not using the big display it's never been a problem as far as stability goes.

[escher]

Originally posted by Dr.Michael:
If you run 1600X1024 the gpu has more load and gets hotter than with the internal 1024X768. So you heat your machine with the cpu, the hd and the gpu. Thats the reason why the fan runs constantly.

I am running in clamshell mode with an external resolution of 1280x1024. I started running ThermographX to monitor temperature. Interstingly, the GPU is always about 10 deg Celsius (or about 20 deg Fahrenheit) hotter than the CPU and HDD.

I don't think that apple has tested their powerbooks with all possible modes of lid closed operations in all possible climates. So I don't think that the technical possibility to do a lid closed operation does also mean its always safe.

That certainly makes sense. Thankfully, any place where I am likely to run in clamshell mode (including home and office) has central A/C. So I am unlikely to come anywhere close to a clamshell worst-case scenario.

Escher

[Dr.Michael]

Originally posted by escher:
I am running in clamshell mode with an external resolution of 1280x1024. I started running ThermographX to monitor temperature. Interstingly, the GPU is always about 10 deg Celsius (or about 20 deg Fahrenheit) hotter than the CPU and HDD.

Hi Escher,

thats interesting. Can you post numbers about gpu temps with a number of resolutions (only internal, only external 1024X768, 1280X1024 and 1600x1024) and monitor spanning mode?

I only have the phenomenological experience with the fan and gpu heat. Numbers would be great. I don't have access to an external display otherwise I would do it myself.

Greetings,
Michael

[TailsToo]

Originally posted by Hanul:
I'm a little bit skeptical with my 12" PB. I always open the lid a bit for better air flow over the palm rest, where the HDD can get hot. When opening the lid *after* setting up the external display the internal one stays turned off.

I do the same with my 15" I can get quite warm when closed, so I figured that it would be better to open the unit a bit and let it get more cooler air. If nothing else, it keeps the fans running less often!