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I've had one of these under my 15" PB for three years. I only ever hear the internal fan come on when I take the laptop off the thing. I have one with a 4-port usb hub built in, with two variable speed fans. I'm also Folding 24/7 on this PB, so you know the coolpad works.
 
I've had one of these under my 15" PB for three years. I only ever hear the internal fan come on when I take the laptop off the thing. I have one with a 4-port usb hub built in, with two variable speed fans. I'm also Folding 24/7 on this PB, so you know the coolpad works.

how noisy was that thing?
isnt it better to get one with just one big fan?
any model you would recommend for a 15" MBP?
 
You need to look for something that draws air away from the base, and also the fan does not blow down, but rather there should be vents on the base that allows you to use the cooler on a bed or something.

Don't get the LapCool4 because it blows air down.

I have this one:
http://www.newegg.com/Product/Product.aspx?Item=N82E16834998378

It's pretty quiet for most purposes. If you look at the third product picture, that's the kind of output vent you should be looking to get.
 
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