"Aluminum cases have also been billed as a way of reducing system temperatures as aluminum conducts heat about 3 times more effectively than steel which is what most cases are made of, and while this may help in a case with VERY little or no airflow through the case, I found temperatures using the Lian Li where only 1c lower than in the Globalwin 802 and 4c lower than a generic ATX Mid-tower."
This must be why aluminium is used on SFF cases.
If you are thinking of paying the extra cash for a case just remember that you normally do not get a power supply included with these cases.
A budjet case in the uk costs around £30-£40 a Lian li around the £60-£70 mark then for fancy ones upto £200,so a difference of £30 max but you get better build quality for your money (than a budget case)and normally 2 or 3 system fans with filters on the lian li cases...so the £30 difference is reduced somewhat if you take of the cost of fans and filters.
I just did a total system overhaul and I purchased a Chieftec Aluminum tower with window mod, and 420watt power supply from NewEgg.com for US$95. A little more expensive than your average steel case, but certainly a lot cheaper than the US$175+ prices of, say, a Lian Li case... and that's not factoring in the cost for a power supply.
I'm no physics major, but I can tell you using the same ThermoEngine Heatsink w/7K rpm Delta 60mm fan, my system runs about 20-25 degrees F cooler now than it did with my old In-Win Full Tower Steel case.
That may be in part to the newer Athlon processor (2700+ vs. older 1800+), but I'm certain a great portion of that is the dynamics of an aluminum chassis.
Different construction in cases make a big difference in temperature. The only way to compare is to have two identical cases, one in steel and one in aluminium and then compare them. I still don't think it makes much different.
Please prove me wrong if you want to, would be good to know.
basic physics dictates that metal is a good conductor of heat... therefore it will transfer heat from a high gradient to a low gradient...
translated to a computer case... the air inside is conducting heat AWAY from the cpu (the hsf spews out the heat into the case) and your exhaust fans get rid of some of the heat from this... however the case temp is warmer than the exterior temp... the interior of the case will warm up as a result and the transfer of heat from the interior to exterior (high to low temp gradient) will "remove" the heat from the computer's interior...
the overall conductivity of the case is not in question... but the actual amount of reduction in interior temp is not that much greater than a regular non-aluminium case with good cooling (intake/exhaust fans)... if you have a good cooling setup... don't really need the aluminium... but it does help out...
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS