more on: Overheating problems with long continuous use?

[Ted Frederick <tedf@cadence.com>]

At 11:13 AM 3/8/96 -0800, you wrote:
>I keep it up on the feet so air can get underneath.  I guess there is some
>dissent about this, someone on the list suggested that something hard like a
>desk is a better heatsink than air, but from usage, it gets hotter when it's
>flat on something, and especially if on something soft, like a lap or any
>cloth type thing.

The case may seem cooler when it is up on it's feet, however, the processor
will be hotter.  

The high temperature of the case when you have it on a solid surface (other
than, say a lap or styrofoam) is indicative of a preferred 'heat path'.  I
used to do this stuff for a living at Compaq several years ago, so I won't
bore you with the physics, suffice to say that if the surface is even
moderately conductive (wood or formica) you will get better thermal
performance than just relying on free convection with the legs out.

I actually use the legs only when it is on my lap.  Room air after all is
cooler than my 95+ degree F lap.

Regards,
-Ted

*******************************
 Ted Frederick

 Strategic Programs Manager
 Worldwide Practice Management
 Cadence Design Systems, Inc.

 T:408.894.2275
 F:408.894.3484
*******************************
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