What material is best placed under a laptop to reduce heat?

[charlie10]

I'm looking for a material to place my laptop on while its on my lap as it gets hot. What material will best prevent the heat? I had aluminium in mind....

 

Thanks

[alpha2cen]

Aluminum alloy is reasonable for hardness. And the shape is important too.

Heat have to be removed from computer to air.

At first computer heat is transfered form computer to aluminum, next transfer from aluminum to air must be established.

At this time convection heat transfer is required, and the important factor for the convection is external surface area and air contacting surface shape.

You can get more detail information from "Heat transfer"book.

[charlie10]

thanks, would there be anyway then to reflect the heat away with a aluminium plate under the laptop? So the heat transfers from the laptop to the plate and then is reflected into the air

[John Cuthber]

"What material will best prevent the heat?"

 

Ice.

[insane_alien]

"What material will best prevent the heat?"

 

Ice.

 

hydrogen ice

[John Cuthber]

Frozen hydrogen in a vacuum chamber.

[TonyMcC]

I don't know what it is made from but you can buy simple cooling mats for laptops and also some incorporating fans that can still be used on your lap. Google "NEWlink Laptop cooling" for one example.

[michel123456]

Nothing. Let air circulate.

[Cap'n Refsmmat]

I don't know what it is made from but you can buy simple cooling mats for laptops and also some incorporating fans that can still be used on your lap. Google "NEWlink Laptop cooling" for one example.

 

Indeed. There are quite a few products designed for this purpose. Here's some from Newegg:

 

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007639%20600028834&IsNodeId=1&name=Cooler

 

As for specific materials... I believe aluminum and copper are often used for heatsinks. You'd want to get as much metal as possible in contact with the bottom of the laptop, to conduct the heat, and as much surface area of metal exposed to the air as possible, so it'd cool down. Of course, you might just end up with a cool laptop and a hot sheet of metal, which is why the various laptop coolers use fans.

[StringJunky]

A flat stiff board of wood or plastic should suffice....you should just need a clear space under the laptop like that when you leave it on a table top to allow air intake....does it overheat on a table? If it does your fan and heatsink probably want cleaning of dust and/or reseating with new thermal paste.

Edited December 18, 2010 by StringJunky

[Cap'n Refsmmat]

Indeed. If the laptop's more than a year or two old, definitely look into cleaning out the heatsink. I had a four-year-old laptop that I disassembled (Dell provides disassembly instructions for all their laptops on their website -- you just need a screwdriver and some patience) and the heatsink was almost entirely clogged with fuzz and lint. Once I cleaned it out, the laptop was miraculously much quieter and much cooler.

[StringJunky]

Indeed. If the laptop's more than a year or two old, definitely look into cleaning out the heatsink. I had a four-year-old laptop that I disassembled (Dell provides disassembly instructions for all their laptops on their website -- you just need a screwdriver and some patience) and the heatsink was almost entirely clogged with fuzz and lint. Once I cleaned it out, the laptop was miraculously much quieter and much cooler.

 

The sonic transformation does indeed seem miraculous when it's sorted...if the system fan is going full speed trying to compensate for the restricted airflow an uneven obstruction of lint and dust can knock the fan blade off balance and make it sound like it needs replacing when it doesn't. I've learnt the hard way to always buy a laptop where the fan/heatsink asssembly is accessible from the back and not from the top which can take ages and much cursing moving other components out of the way!. Given that laptops are placed anywhere, including linty and dusty surfaces, like clothes, being able to clean the fan assembly easily is important IMO.

[Ludwik]

Nothing. Let air circulate.

 

I agree. But make sure there is a layer of air (5 mm is enough) between the laptop and the table. This can be done in different ways, for example, by taping four short "legs" to the bottom of your laptop.

 

Ludwik Kowalski (see Wikipedia)

[John Cuthber]

Go into your local electronics supply store and, in a loud clear voice, ask the sales staff "Do you have sticky rubber feet?".

Even if you don't get something to hold your laptop clear of the table, you should get a laugh.

[michel123456]

I agree. But make sure there is a layer of air (5 mm is enough) between the laptop and the table. This can be done in different ways, for example, by taping four short "legs" to the bottom of your laptop. (...)

 

You need convection to take place. 5mm is (as much as I know) an empirical minimum. (edited)

 

Ludwik Kowalski (see Wikipedia)

Impressive.

Are you the real one?

Anyway, welcome.

Edited December 21, 2010 by michel123456