Will black aluminium make it run hotter?

TailsNZ · Post by **TailsNZ** » Fri Jan 16, 2004 2:05 am

I'm planning on getting the Lian-Li 6070, which comes in silver or black... I'd prefer to get the black, but will that make much of a difference to heat? It won't be sitting in direct sun, but of course they'll be a lot of heat inside the case.

ashtray_head · Post by **ashtray_head** » Fri Jan 16, 2004 2:10 am

I wouldn't of thought it would make any difference at all......but hey who knows?

anyone else got any ideas?

chylld · Post by **chylld** » Fri Jan 16, 2004 2:17 am

No. the colour is irrelevant.

if there are any differences you wouldn't be able to measure them anyway, they'd be miniscule.

Choy · Post by **Choy** » Fri Jan 16, 2004 2:19 am

All colours absorb and emit energy equally so it doesn't matter. To make it a bit more clear I mean that black absorbs and emits equally, while silver absorbs and emits equally, but at a different level with the net effect being the same.

Hope I didn't confuse you, I was myself for I while

ashtray_head · Post by **ashtray_head** » Fri Jan 16, 2004 2:27 am

Choy wrote:All colours absorb and emit energy equally so it doesn't matter. To make it a bit more clear I mean that black absorbs and emits equally, while silver absorbs and emits equally, but at a different level with the net effect being the same.

Hope I didn't confuse you, I was myself for I while

thanks for errr...explaining that

Bluefront · Post by **Bluefront** » Fri Jan 16, 2004 3:19 am

Errr....I think there is some mis-information going on here. Dark colors do absorb heat better than lighter colors. It has to do with reflection. Test it yourself. Place your hand on the roofs of cars all sitting in the sun. You'll find the darker colored cars feel much hotter than the whites or silver ones. Blacks, reds, always feel hotter.

Also....dark colors cool more quickly from the same temps when the heat source is removed, or when a fan is blowing over them. This is why cooling fins on racing motorcycles were usually painted black. I'm sure there is a detailed explanation of this effect on the Web somewhere...

As far as colors of computer parts affecting temps..the differences are probably insignificient.

miker · Post by **miker** » Fri Jan 16, 2004 4:02 am

It would only matter if the PC were left out in the sun. Color only affects the heat absorbed from heat produced by light. In a dark room, a white PC and a black PC will behave exactly the same.

Sledge · Post by **Sledge** » Fri Jan 16, 2004 5:02 am

I was just reading a book about Lockheed's Skunk Works. In the chapters where they were designing the SR71 Blackbird, Ben Rich the thermodynamicist (and the author) wanted to paint the plane black because due to radiation heat transfer the plane's skin would be 30-40 degrees F cooler.

But understand that radiation heat transfer really doesn't do much work until you get close to four digit temperatures. Are you running an Intel Prescott?

Post by **Ralf Hutter** » Fri Jan 16, 2004 5:42 am

Sledge wrote:But understand that radiation heat transfer really doesn't do much work until you get close to four digit temperatures. Are you running an Intel Prescott?

Or one of those 90nm AMD Hammers?

lm · Post by lm » Fri Jan 16, 2004 6:41 am

miker wrote:It would only matter if the PC were left out in the sun. Color only affects the heat absorbed from heat produced by light. In a dark room, a white PC and a black PC will behave exactly the same.

If the case of the PC was very hot, the black case would radiate it's heat away faster than the white PC. But since the case of the PC will not usually get hot, it does not matter. The case has so much contact area with free air that it's enough for cooling the case itself.

NamJangNamJa · Post by **NamJangNamJa** » Fri Jan 16, 2004 7:09 am

It wouldn't matter unless it is exposed to direct sunlight.

TailsNZ · Post by **TailsNZ** » Fri Jan 16, 2004 12:48 pm

Fantastic, thanks for all the replies. No liquid nitrogen needed then... (isn't that what Intel R&D used to develop their future chips for awhile? Yikes!).

Now before I order the case, I'm just gonna go through and read the old topics on the 6070. From what I've read so far I think I'll need to replace the stock fans.

silvervarg · Post by **silvervarg** » Fri Jan 16, 2004 3:14 pm

lm is correct here.
Black will radiate heat better than silver for instance, and it does not just effect heat from sunlight etc. But there is one more thing to the equation: a silver aluminum case is typically not painted, while a black case is painted. The paint layer will have an insulating effect that might eat up app of the advantage of the black color (assuming the paint was not specifficly choosen for its thermal abilities).
So the total net is that we can't really tell what version of the case will run cooler. The thing we do know is that the difference will be very small (a fraction of a degree with anything close to normal cooling).