An Idea That Might Work

[lbmagic]

OK i was extremely bored in class today and i noticed that my pen had rubber silicon in the grip so took it out and put it on the power supply for my laptop. 10mins later i remember i put it there and took it off, then i noticed where i had it the power supply was cool instead of its usual extremely hot self. Also i noticed the silicon was hot and had absorbed the heat from the power supply.

 

So then i thought that maybe if i bought some silicon rubber and put it on the heat sinks on my motherboard, it would absorb the heat from the sink. Then to top it, i could place a small fan on the silicon which will keep the silicon cool which lets it the sink absorb more heat and let the silicon absorb more heat and keep cool. Does this sound it would work? A new revenue of cooling

[kingdingeling]

It sounds more insulating than cooling to me...

[ARandomOWL]

It's not gonna make much diff to ur HS. Copper/Aluminium is much better, thats why it's used in HSs

[scr4wl]

It's not gonna make much diff to ur HS. Copper/Aluminium is much better, thats why it's used in HSs

 

I think he means on top of the heatsink so that the silicon abosorbs the heat off of the heat sink.

 

heat>heatsink>silicon

[lbmagic]

I think he means on top of the heatsink so that the silicon abosorbs the heat off of the heat sink.

 

heat>heatsink>silicon

 

yeah that's exactly what i mean like it wouldn't harm to try right? And with the fan ontop would work even better so:

 

heat>heatsink>silicon>fan

[Crazy_Nate]

Thermal conductivity of silicone: 0.146 -0.314 W/(m^2 K)

 

Thermal conductivity of Aluminum: ~237 W/(m^2 K) (room temperature is approximately 293K)

 

 

When you're thinking about heat transfer, ALWAYS realize that heat has to go somewhere. Take care to note that it will never go from a lower temperature to a higher temperature.

 

So...you have two choices. The heat goes from the processor to the heatsink to the air (in order of decreasing temperature). Or, in your case, the heat goes from the heatsink to the silicone to the air. However, compared to aluminum, the thermal conductivity is abysmal, meaning it will require a greater temperature drop to transfer the same amount of heat through your hypothetical design. This means, your processor will run hotter.

 

Or...I guess there could be a third case. The silicone is cold to begin with and then it "absorbs" heat. In order to absorb heat, its temperature will change. However, heat transfer is proportional to the temperature drop in conduction. As that temperature drop decreases, it becomes "harder" to transfer heat and you're back at it being severely limiting to the heatsink's performance. These transients are what account for your processor not reaching maximum temperature instantly when you apply 100% load. The system hasn't reached steady state yet...

[hardnrg]

lol... to sum up what Nate said...

 

silicone = fail

 

metal = win

 

 

 

your idea isn't bad though, there are several commercial products (that use silicone absorption) available on the market that act as a heat absorber for laptops... a type of passive heatsink... it's like a gel cushion that sits beneath the laptop and absorbs heat without the need for power... but it only works for a few hours (this will vary on heat output)

 

it's not a bad solution for short periods of time, but because you can't really actively cool silicone, it won't really work for extended periods... then, the "old-fashioned" USB-powered active fan cooling will be superior and more effective...