no problem just wondering

[Abbadon]

Lately I've been digging into the entire cooling / airflow stuff and I'm puzzled about something:

When you install a vidcard in in a towercase it has the fan & heatsinks pointing downwards (that is, on all cards I've seen so far). But since hot air goes up, all the hot air that is blown down from the card by the fan just rises up again straight into the card (well, of course not all of it as most will be deflected by the stream of air comming down, but you know what I mean ;) )

Wouldn't it be better heat management to put the heatsinks and fan on the other side of the card, directing the hot air up from the vidcard and (in my case anyway) towards the fans sucking air out.

I'm probably overlooking something, but the way I see it the current design is just not optimal airflow.

Anyone capable of clarifying this?

[Whyzman]

To add to "The Mystery," why do some Vid Card manufacturers produce things like limited edition cards with awesome looking custom fans (great "eye candy"), only to have them install in the same position you mention where you cannot see them??

And, with cases designed to allow viewing the innards, the "eye candy" doesn't sweeten the look, but rather sours the whole concept...:(

[Steve]

Heh heh...This weekend, I was putting together two new boxes and was wondering the very same thing. The only thing that I could come up with was that if the card was reversed, it would be blowing the hot air off the video card right at the processor.

I doubt that is why cards are designed that way, though. All the cards I have used have the face pointing down. NIC, sound, video, etc...All except that old modem I've got. :confused:

[Budfred]

I'm guessing that they designed cards originally for desktop rather than tower boxes and they now just have a tradition of doing it that way. One day a designer who is also into modding towers will realize that it doesn't look cool the way they are doing it and it doesn't cool properly either and design a card that does look and work cool.... That card with sell out all over the place and a new tradition will be born... Then in a few years, people will be wondering why they were designed that way.....

[gwallen4]

Hmmm. Doesn't the heat sink/fan usually blow the air toward the chip (up) rather than away from it (down)?

Anyway, the purpose of the fan is only to make sure that some air circulates through the heatsink.

The ATX specification for cases came out before processor heat was a big problem. Heat dissapation was a big consideration in the design of the new specification - the BTX (balanced technology extended) form factor:

http://www.anandtech.com/showdoc.html?i=1876

[sleddog]

To add further to the mystery: when assembling a PC, why do some (bad) shops install a PCI card in the first slot, tight to the AGP videocard with fan, and leave 4 empty PCI slots further away from it? In a year the video fan dies of heatstroke in that impossibly confined space, then the videocard overheats, stuff crashes, and you bring the machine back to the shop for repairs, where they charge you a week's salary to stick another little fan on. Oh wait, I guess that's the answer :)

[Whyzman]

"Planned Obsolescense" = "Job Security" ;)

I would agree Budfred, that someone is going to "catch-on" and switch one around so you can see it's "eye candy" fan and revolutionize the industry...:cool:

[Abbadon]

Gee, I wonder if this idea is pattented already. If not, and if Budfred is right, there's some sweat money to be made :D

[malcore]

If video card fans blow air onto the GPU (which they do) and hot air rises, wouldn't having the fan on top be pulling warmer air from the upper part of the case onto the GPU? Also, with the location of the card in relation to the CPU in the present ATX format, wouldn't the CPU fan and the GPU fan be competing for air from the same area, thus producing a "dead zone"? And, with hot air emanating from the area of the CPU, would a fan on the top of a graphics card not be pulling that hot air onto the GPU?

I think this is another reason for the move to the BTX format. With the heat produced by present high-end systems and the ATX format, we now have the CPU fan, rear exhaust fans and fans on the bottom of PSUs all pulling air from the same area. Not very efficient, and to add the graphics card pulling air from that area would only exacerbate the problem.

Maybe card manufcturers will design their cards for the new BTX format to display the "eye candy". I doubt it will happen for AGP cards in an ATX case, unless the direction of air was completely rethought.

[Abbadon]

Well at least this is a good reason for having it the way we're having it as it is. For some reason I always thought that the fans sucked hot air away from the GPU (dito for CPU) so I learned something today! Jay! :D

Incidently, I am going to sue you for messing up my patent-idea ;) :p

[Whyzman]

Incidently, I am going to sue you for messing up my patent-ideaHold on there a sec...:)

I think I should be able to "patent" my "That's sure a dumb concept" when I viewed a special edition Chaintech AGP card touting a really cool chrome fan setup at least a year ago...

I remember saying to myself, "That's a patently dumb idea...who's going to see it once it's installed!? Why don't they design it so you can see it...flip the thing over!?" :(

So, as you can see, I was already stirring the intellectual property pot...:D

[Budfred]

It would be quite feasible to create a cowl/funneling system to direct the air in and out of the heatsink any way that would work most efficiently and still make it look cool, so the idea is still a valid one, but may not be done since BTX is about to become the dominant standard....