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Painting Heatsinks?????????

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You should be fine. It will effect temps. Will you notice the temp difference ?? Nope. Will it affect your overclock, probably not. I would never paint a CPU/video card heat sink, but eveything else is pretty fair game. They do not put out too much heat.
 
OMG dude dont paint it , u will fry your Nbridge b/c paint doesnt transfer alot of heat. its gonna cool your nbridge as much as a plastic heatsink :D
 
flat black is the best heat transfering paint...hence why your car engine compartment is in flat black and race engines are painted flat black ;)...
 
glock19owner said:
flat black is the best heat transfering paint...hence why your car engine compartment is in flat black and race engines are painted flat black ;)...

That was actually the most intresting thing I learned all day. Does it only come in black? Or is that just the product name.
 
I think he meant flat black paint, as in not glossy, and not purple, but just plain flat black paint.

I dun know if this is true for transfering heat, I know that it absorbs the most light, thus producing heat, however light has nothing to do with cooling a northbridge, etc..

I could be wrong of course.

BTW, old car engines used to be orange, heh.
 
flat black is just a automotive term name for plain black paint...sorry for not clarifying that...and yes...it is the best heat transfering paint...I used to be in automotive and used to race my 68 charger...and if you notice...F1 and IRL, Cart, NHRA, etc, engines are all flat black (block and heads)...and this is why all black car interiors get so hot while sitting in the hot sun all day...it conducts the heat inside of the car...hence also why all of the hoses are black also...helps cool down the coolant...

And yes they used to be orange until they found out that black conducts heat better then colored paint...

ADDED: This is also why the oldier metal HS's were painted black also...
 
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you should not paint your heatsinks because paint doesnt transfer heat very well. The older different colored heatsinks are painted using adonized paint, which doesnt interfear with heat transfer as much as regular paint. however it still does. this is why high preformance heatsinks (SLK series) are not painted
 
drunksquirrels said:
you should not paint your heatsinks because paint doesnt transfer heat very well. The older different colored heatsinks are painted using adonized paint, which doesnt interfear with heat transfer as much as regular paint. however it still does. this is why high preformance heatsinks (SLK series) are not painted

They are not painted because they are not steel and total copper (SLK series like you used for your example)...which does conduct heat better then a flat black old metal HS...but since they are using aluminum...that really will not come into play all that much...now if it was a all copper heatsink...I would of definetly told them not to paint it...painting a aluminum HS will not effect the heat transfer all that much...might help it...might hurt it...but not by much...maybe 1 to 3c if that much...and you are right about adonized paint not being that transferable...that is why I did not mention it...flat black will transfer the heat better...but once again...not by much...but it will look a lot cooler...especially if they have a window...
 
i painted my volvano 6 hsk from blue to red didnt notice a differenc in temps @ all just paint the out side not the middle your not gonna see the middle any way
 
From my understanding, glock19owner is right. But i have also heard that matte black, or flat black, paint conducts heat the best. both absorbs and releases heat the best for being painted. i dont have a definite source for this info, but it is what i heard.
 
Don't paint it, paint will hinder heat transfer because it is another layer that has to be overcome. The best way to cool anything is to limit the number of heat paths the heat has to go thru.

All this talk about black paint helping in heat transfer is all snake oil when it comes to cars. The top teams in F1 like Scuderia Ferrari, BMW Williams or McLaren Mercedez dont paint there engines. Hoses are black because the chemicals mixed in to the material they use for hoses have high carbon content, not for cooling. The reason why you have radiators in F1 cars in naked Alu becaue you dont want a secondary heatpath, further proof is that the Air - Air Intercoolers on high performance turbo cars are still in naked Alu.

Black does absorb heat more than any color from either a light source or radiated heat & also releases them just as well. The difference is not significant enough to matter in any system so it is done for pure cosmetic reasons.

I'm sure someone will raise the point of why ALPHA NOVATECH Anodize their heatsinks black. I suggest you email them & find out why they think its a cosmetic addition as well.
 
Sonny said:
All this talk about black paint helping in heat transfer is all snake oil when it comes to cars.

So I guess my automotive books about cars engine compartments being black for a reason are wrong and that my old charger actually ran coolier when it was painted flat black compaired to when it was painted all orange was wrong also...and if you have ever been to a NHRA event and been in the pits...before they had these aluminum blocks and heads out...guess all of those racers where wrong for painting there blocks and heads all black...No...there was a reason why they did that...and that was because it did lower the temps...

And I was not talking about todays F1 and Cart and IRL and NHRA...but up until a few years back...well before cart...they did used to paint there engines flat black (when they used cast iron blocks)...and this was to keep the engines cooler...no offense sonny...but you stated that race cars are one of your interest...if so then you would know about how they used to paint their engines and heads flat black back in the days to keep the engines running cooler and lasting longer during the longer times it took to finish a race back then...I started drag racing back when I was 16 up until about 6yrs or so...when my daughter was born...she came first before my car and harley...so yes...flat black does help and it is not just snake oil as you call it...

Not getting personal...just proving a fact about flat black...with todays all aluminum engines and heads...no they don't...but at a time they did...and they did for a reason...and if it wasn't true about the engine compartment...then why are 90% of the cars made today still have the black engine compartments...why...because it does help absorb the heat away from the engine...

Once again...not getting personal...so do not take it as a personal shot to you...just your comment about flat black being snake oil as you call it...

And yes I was wrong about the hoses...but since I do not make them nor never will...didn't think about the chemical changes that take effect...but it still comes down to...it changes black and still helps absorbs the heat of the coolant...so in theory it still works...
 
I would rather trust todays technology compared to a few years ago when it comes to car racing technology. They stopped doing that because it wasnt working as much as people thought. The painting of engine bays flat black has stopped in my coutry. I live near the equator & have very high ambient temps. Just 98% of the cars here have body color engine bays. The Mercs that have black engine bays are the ones that overheat more often than any other car. Why has the practice been discontinued in the more advanced formulas? Why are real race parts like radiators or intercoolers unpainted. Convince someone that races a car that runs over 2Bar of boost to paint his intercooler black because it will cool the air better, see how far you get with that.

Todays technology is far superior to yesterday. Yes race cars have been a very big part of my life & the one thing that I have learned is that if you don't keep up with technology then your left in the dust. Today that they dont bother with painting it black, that says something about practices in the past.


EDIT: To bring this back into topic here is what ALPHA has to say in their Q&A,

Q. Which give better performance, black anodized or clear anodized heat sinks?

A. The results of our tests show that when air velocity is low (0.5m/s) black anodized is better. This is thought to be because the black color dissipates more radiant heat. However, if some other heat source is located near the heat sink, the black color will conversely easily absorb radiant heat, so the choice must be made depending on the environment.

Now email them at [email protected] to get a more detailed answer.
 
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Ok, for all you car bickering people. Chevy engines were painted orange, fords were blue, those were their colors. The reason that racing engines were painted flat black (not saying it does or doesn't transfer heat better or worse) is because it makes it very hard to make out any details of the engine compartment. Racing technologies are very secret, that's why you see the suspension components and downforce components on F1 cars painted flat black, so that they don't give away their secret. Not saying who's right or wrong, just my two cents. Oh - paint that heat sink with a light coat of paint, then lap the bottom to remove the paint. You'll get the looks, a freshly lapped HS, and you won't gain too much in the temp dept.
 
Black itself, flat or not, gives the best transfer of any color. Painting it should not make any huge difference as the alumnium has a fairly low heat transfer as compared to copper. Go ahead and paint it.
 
I would like to think differently on painting a heatsink...even just the parts except the base becuase say when you have a fan blowing on it, or air passing over it from the case fans blowing that is yet another layer for the heat to transfer through on its path to the air. If the heat is going fine to the base, then to the pins/fins on your heatsink, it is in the metal and going to transfer to the air, it has to transfer through the paint also, which probably isnt the most efficient way to get it to the air thus keeping some heat actually on the heatsink instead of removing it...

I could be thinking wrong, but this just seems to make sense to me.

Fold and Frag on
Brian
 
Paint acts as an insulator, it will interfere with heat transfer. Is it significant enough to matter. Probably not for your usage. There are non-insulating paints for electrical applications. I don't think its worth going to that extreme.
 
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