Graphics Cooling fans on Graphics cards

In my couple of years of heavy computer building and modding I've noticed that Most of the High end graphics cards Have a huge HSF/Fan on the PCI slot side of the card and then you loose one posibly two PCI slots. Does any one know why Graphics card manufacturers put the chipset and cooling on that side when i've never seen a mobo that has anything close enough to the agp slot that would worry the card if the built them on the other side.
The only problem i can see is if they have an external exaust in which case they actually need a pci bracket.

 

Yeah, i've allways wondered why it's like that too. If the card was the other way round you'd be able to see the heatsink and fan better, which i think would look a lot cooler
But there must be a reason, you would think.

 

since hot air rises, if a card was the other way down the following would happen
>fan pulls air down from above, blows on card
>air gets warm from card
>air rises
>fan pulls same air down
>air gets even warmer
>air rises
>fan pulls same air down again
>air gets even warmer

etc etc etc, i think you get the idea
the fan on the card pulls cooler air from below the card, blows it on the heatsink, the heatsink channels the air to the ende of teh card at which point the warm air continues to rise through the case

the new BTX form factor being developed changes the position of the CPU and graphics card so that hot air from the card does not rise straight up to the CPU, when the ATX for factor was designed many moons ago, graphics card generated marginal heat so there was no worry about heating up the cpu

in BTX, the graphics card will, however, remain with the heatsink facing downwards

 

It may well increase tempratures changing the orientation.

The way ATX specification works is to pull cold air in at the front of the case, for your graphics fan to push nice cold air onto the core and excess heat rises up to the top of the case and out the rear ventilation.

If you turn the card over the heat from the CPU/warm rising air will be pulled back down and the graphics card, GPU core cooling could be worse.

 

How big a temp increase do you think there would be? In a standard set up, neither the cpu or graphics card should produce enough heat to cause a problem. and in most modded/overclocked systems there's extra ventilation to accomodate for any temp rises, surely ensuring that a 'flipped' agp card wouldnt cause a problem either. Obviously, I can see why it's done the way that it is, but do you really think it would cause many problems if it were the other way up?

 

the reason it is the way it is, is because it's the best way to do it
it wouldnt couse a meltdown if it was the other way but it wouldnt be as effective
in modded and overckocked systems people usually strive for the best temps possible, so having a graphics card upside-down would be contrary to this
and besides, i dont think the people that create the specifications could care less if it looks cool or not, it should work the best it can
hell, it would be pretty sweet to have the graphics card outside the case, that would give you a good look at it, but it just doesnt make sense now does it?

cars have the driver's seat in the front because it makes the most sense and is the best way of doing things
you *could* put a wheel in the back and still drive, but it just doesnt make as sense

 

to be honest i bet it wouldn't change much if at all...

think about people running wATX, the CPU being below the video card, and they reportedly get the same temperatures as a standard ATX setup...


also, since motherboard manufacturers aren't held to positioning certain things in certain places as far as above the slots goes, there is potential for blocking the slot above... i know for instance that on my EPoX that the ATX cable, as well as memory slots are extremely close, as is my northbridge heatsink to the back side of my AGP card... but since there is a standard on the distance between slots on a board (since cases all have the same amount of space between them and the ATX backplane IS standardized, you can gaurantee that there's a certain distance between the AGP slot and the nearest PCI slot.

 

HARDLY a valid comparrison.

 

i think i was taking the piss if i remember correctly

i think my point is, the reason it is that way, is because it works
and remember when the ATX form factor was introduced graphics cards didnt have fashy heatsinks, cases didnt have windows and CCFLs

i have turned my case upside down for a bit just out of curiosity
im going to run 3dmark03 for a bit and see if that does anything to the temps

 

Cools. Remember to post your findings.

 

i decided to play unreal tourney 2k3 instead for a while and it did get a few degrees hotter
GPU topped out at 67C wheras i normally dont see it over 60C

that may just be because the airflow was different when upside down, but the CPU temps were pretty average

mind you, these arent really proper results as any amount of things could have affected it with the case being upside down and all and the airflow was undoubtedly messed up a bit

 

If said gfx and cpu were this way (ie gfx facing up and CPU as is mounted vertically above GPU), would it not make sense to rotate ones fans so that they pulled away from said GPU and CPU and extracted at the top on ones case? (blow not suck )

Personally I would have thought this would make more sense than the dead air around the lower edge of the gfx card.. Or gfx/cpu pulling in hot air from each other.

GPU pulls/pushes hot air up…. As does CPU pulls hot air/pushes it out.. Hot air rises.. at top of case place 1/2/* fans pulling out. (hopefully matching/less than u are pulling in)

Granted your CPU may have a few issues with this layout, but if you have a few fans pulling in fresh air around it then that should more than compensate? I would expect the GPU temps to drop tho, not rise as per Mister_tad exps? CPU temps I would expect to rise slightly.

but this may just be me

Laters
Jon

 

Well i recon that if you worked it out properly you could have holes through the card to draw air from below over the heatsink and then through the fan. and this would probably work better cause for some reason sucking air over a heatsink is better than blowing which is why car radiator fans are behind the radiator. And also in that pocket of air between the CPU HSF and the Graphics card most cases I've seen have an exaust fan so it wouldn't be reusing the same air any way. And having the chip on the opposite would be a lot better for water cooling setups also in order to save precious PSI slots.

 

That is exactly what you don't want, remember the the way ATX specification works is to pull cold air in at the front of the case and heat rises up the case and out the rear ventilation.

If you do as you say above you will be sampling hot air near the exaust fan.

This hot air will be comming from the CPU heatsink and the Graphics card its self.

 

Question About Temps

Hi I am trying to overclock my Radeon 9600 PRO and was wondering if some could tell me how you get temp readings? I know some motherboards have temp readers built in, but mine doesn't. Is there a cheap way for me to see my temps besides trying to use a thermometer?

 

Short answer no. Reason being apart from the lastest 9800xt none of the other ATI cards come with inbuilt temp monitors. So you would have to use a temp probe to get a reading.

 

Ok Thanks, I got it without temp anyway, my card has this thing called VPU recover which kicked on when I went to far, made it pretty easier =0. I was able to get clock from 324 to 424 and memory from 192 to 210. Thanks to all of you who post here, your info helped me alot.

 

does anyone what cooler i shud get for my fx 5600 128 mb please would be great if so

 

thanks for the help (sarcistic) any way i got a vantec iceberq 4 works great and my card is much better now