Hot air rises, yes?

[MU51CL]

Hi guys from the Land Down Under.
My first post here, which is something that makes me curious about video cards.....which are often quite "warm" things.....they are generally the most power hungry things in a PC.

As most PC cases are vertical, and my new one will be too, I can't get over something very weird about ALL of them.

When you stick them in their PCI slots, horizontally, all of their heatsinks / fans face DOWN....and hot air wants to go UP.
It seems all wrong to me - anyone shed some light on why this is??

[oralpain]

The change in air density from the 10-20C temp delta is going to be a lesser factor than even low flow fans by orders of magnitude.

Orentation for these things, at least in systems with any reasonable level of active cooling, is almost completely irrelivant.

I can take my entire case, flip it over and the temps remain the same.

[MU51CL]

I like that answer, fair call for sure.

Just looks wrong.

[Meridian]

Isn't one of the big selling points about BTX format that it turns the motherboard (and thus the gfx) over?


M

[TheGlasMan]

I like that answer, fair call for sure.

Just looks wrong.

It is wrong. It is a carry over from AGP, which reversed the orientation of the original pci so idiots wouldn't try to force them in. You may remember the term "shared slot" where an agp and pci card in neighboring slots would use the same backplate hole, ie you could have one or the other, not both. Back then video cards were low power devices, even 3Dfx cards (which were pci) had no heatsinks, much less a fan!!!

Why they haven't reversed things on the board by now is beyond me, maybe to keep the heatsink from interfering with the cpu cooler.

[Brandito]

maybe it's dust, i'd say dust has a harder time collecting under something than on top.

[TheGlasMan]

Since most dust enters from the bottom front, the fan sucking from the bottom of the card just sucks it in.

[Brandito]

Since most dust enters from the bottom front, the fan sucking from the bottom of the card just sucks it in.

or does it. i personally have never seen dustflow mapped out.

still venture to guess the card would collect more dust on top than on the bottom, and not all cards have fans, my sound card doesn't.

[_dangtx_]

i like the cards that exit the hot air outside for a reason. a top blowhole is one of the best mods u can do to your case