[Tech Tips] Fixing an overheating Toshiba Portegé M200 tablet PC (2)

This post has been relocated to http://gawkysblog.blogspot.com.

This is an additional note to a previous post. It is a tip on how to orient the tablet when using it upright (i.e. using it as a tablet on a book stand as depicted below, or held in your lap).

I have found out that the Portegé M200 tablet runs much cooler (and quieter) when the left side (nearest to tab key) or the back side (nearest to function keys) faces up (towards the ceiling) than if the right/bottom sides face up.

GOOD ORIENTATIONS... back side up / left side up


BAD ORIENTATIONS... front side up / right side up


The reason is easy to understand given the design of the cooling system (see pictures). Hot coolant rises up, so coolant circulates much better if the radiator is physically higher than the CPU. If you do the opposite, the heat will tend to rise towards the CPU, away from the radiator, and cooling will be less efficient.

Even if you use the tablet flat on a desk, tilting it slightly in the above orientations, with a book or something, should help to cool it too (I haven't tested this).

[Tech Tips] Fixing an overheating Toshiba Portegé M200 tablet PC

This post has been relocated to http://gawkysblog.blogspot.com.

[rough translation from Japanese]

I've been using my Portegé M200 tablet PC (sold in Japan as dynabook SS M200) for over a year now. It's followed me around the world, and runs through almost all of my waking hours, so it's amazing that it came this far without a hitch.

Just recently, I'd noticed that the fan was running all the time, and the exhaust was pretty hot. Then, all of a sudden, in the middle of a calculation, it just shut down without any warning. No blue screen or anything, the fan just ramped up for a second, and then everything went black, as if I had pulled the cord and removed the battery. I restarted the computer, but it would only run for a few minutes before dying in exactly the same way. I tried running it with low CPU clock, and it ran fine without this problem.

Given this, I diagnosed overheating, and proceeded to clean the cooling system. This computer does not have a fan directly on top of the CPU, but instead, leads the heat to a radiator on the very edge of the computer, and blows air through this radiator. (Photo: The X-shape bracket on the lower left is holding down the CPU. The copper heat conduit tube leads to the radiator on the lower left corner. This radiator is cooled by the main fan.)


I took out the fan and found a huge buildup of dust on the inside edge of the radiator. There was so much stuff there, completely blocking the radiator, that it's a surprise it even ran at all.(Photo: Yellow arrow, area where dust was found. Blue arrow, dust removed with a Q tip.)


After this procedure, the tablet is running just fine.

(to be continued)



+ Opening your notebook will probably void your warranty. Open at your own risk. It should be very easy to fry a chip or two with static.

+ When opening, don't forget the little screw hidden underneath the battery, and the screw in the harddisk case cover. There's another small fan on the lower plate, so carefully remove its lead from the motherboard when taking off the bottom cover.