Passive PC Heat Sinks, will these work for CREE COBS???

CobKits

Well-Known Member

• Mar 25, 2017

• #21

i dont think there is a default intel heatsink theres been literally several hundreds of different intel chips over the last few decades. the one thing that cpu and leds share is both run more efficently when cool so get the best heatsink you can afford

nothing worng with actives. get you up running quick and cheap

people like the passives, they are an investment but are fail-proof and usable for as long as you are still using cobs

 

CobKits

Well-Known Member

• Mar 25, 2017

• #22

Tsilo said:

I don't have equipment to test it or do some advanced sht any experienced users?

Click to expand...

if you cant keep your hand on the heatsink its over 140F/70C and thats getting up there. if you can keep your hand on it continuously its prob 60-70C and your cobs will live a long healthy life

 

T

Tsilo

Member

• Mar 25, 2017

• #23

this kind of coolers. I don't like active cos of sound, it should be stealthy so another idea i have is to use 2 this type of heatsink and glue it on top with thermal paste in theory it will double area but I'm not sure how good is thermal paste join, will it transfer heat good enough to top sink?

fail-proof but never seen failed fan it's really really rear

 

CobKits

Well-Known Member

• Mar 25, 2017

• #24

that should run a cob up to 75+W no sweat

 

T

Tsilo

Member

• Mar 25, 2017

• #25

thermal paste doesn't reduce heat transfer?

got idea from this video to glue 2 heatsinks

 

CobKits

Well-Known Member

• Mar 25, 2017

• #26

reduce? yes it has resistance but its essential

you wont get even heat transfer without it

 

T

Tsilo

Member

• Mar 25, 2017

• #27

but how much? is it still viable? if i do so and try to measure heat most likely second top heatsink will be cook but maybe because it doesn't transfer heat well enough. can I touch led surface?

 

frica

Well-Known Member

• Mar 26, 2017

• #28

Tsilo said:

thermal paste doesn't reduce heat transfer?

got idea from this video to glue 2 heatsinks

Click to expand...

Thermal paste tranfers heat better than air.

So unless both aluminium surfaces are completely flat (not going to happen), thermal paste helps with better heat transfer.

Always try to have it as thin as possible because it only needs to fill the airgaps.