Can someone please explain the intake/exhaust pattern for a 5970?

Hi guys. Got a quick question about my 5970. Do the vents on the fan end of the card act as intakes? Or do they blow air as well. I'm not sure if the fan pulls air in from both ends of the card then blows it out of the fan or if the fan pulls air in from the end of the card then blows it down the card to the other end and out the front.

Any help would be greatly appreciated.
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More about explain intake exhaust pattern 5970
  1. The fan pulls some air in those vents. It helps cool some of the voltage regulators. Air is then pushed past the 2 gpus and out the back of the case

    If you look at this picture, you can see there is a intake space under the blower/fan, so some air is pulled from the vents behind the fan.

    This is a 5770, but the idea is the same

    There are some cards with a Center fan/blower, those blow hot air out both ends instead.

    Here is a link to a page with an image of what should be your heatsink. Note the intake under the fan pulls air from those back vents

    Top of your card if it had no shroud(it would not work without it),700012/Radeon-HD-5970-Hemlock-in-the-nude/Practice/&menu=browser&image_id=1224154&article_id=700012&page=1&show=original
  2. Ok I think I understand...sorta lol.

    So by the image below, air is being sucked into the right end by the fan and blown out the left end, is that correct? Or am I still wrong?

  3. Yup some air enters the fan and those red vents(attached to the other side of the fan) and it goes out the left side. Hold your hand at the exhaust vent while gaming. you will know its working :)
  4. Great. Thanks for clearing that up for me. I got a little confused by a video from on the 5970 that said the red vents on the right side were exhaust. This didn't make any sense to me because that would be blowing hot air straight back into the case.

    If that end was exhaust it seems to me like it would be going against the intake fans of the case considering that end of the card is only a few inches from the intake fans of most cases.
  5. There are some cards with a central fan, those blow half the heat into the case.

    Like on a 6990,2878-2.html
  6. I was looking into one of those PCI slot fans and thats the reason I was asking. From reading reviews, people seem to like placing these fans below their GPUs, but that doesn't seem right to me? They draw air downward and out the case, but if the GPU fan is trying to suck air in, wouldn't they both be working against each other?
  7. Yes it would. Many used to use those when cards released hot air into the case. With cards that send air out the back, it does not help.

    Your best way to keep temperatures down is to clean the heatsink often(with an air duster).
  8. Great. I really appreciate your help. I have been trying to get my 5970 temps down as absolutely low as possible so when I overclock, I'll be that much better off. They're not bad right now. Most reviews I read seem to report their 5970 idling at around 50 whereas mine stays around 39 at idle.
  9. There are gpu cores on there, one runs hotter, maybe they list the hotter one?

    If you want to push real hard clocks, look into after market heatsinks(there is even water cooling options). They dump heat into the case(well not the water cooling), but the also lower temperatures allot.

    Takes 3 slots instead of 2, very cool and quiet

    Only for the real hard core :)
  10. Yeahh I don't plan on doing a massive over clock. I really only want to get to 5870 speeds. You think thats doable with the stock cooler?
  11. Every card is different, but chances are they lowered the the clocks like they did because it would be lots of heat for the fan to dissipate. You will have to take your clocking slowly.

    The more airflow you have in your case, the lower your overall temperatures will be and overclocking loves lower temperatures.
  12. My case has amazing airflow being a full tower. My 5970 idles at 34c. I've got 2 high flow intakes blowing right into it. Besides, 5970 coolers are ridiculously hard to find.
  13. Your temps seem very good, how are the load temps?

    If you did go the aftermarket cooler path, the Accelero XTREME 5970 is still the best(mostly quiet, you can get very good performance from stock, but require very high fan speeds).
  14. My load temps usually float in the low 70s. Atleast in BF3 that is. I have never actually done stress tests to monitor them. I just always assumed since idle was so low obviously the fan was doing its job correctly.
  15. I Wish my case was that pretty inside. Between my radiator with dual 120mm fans, the other 6x120mm fans, 6990 and 6970 power cables, molex powered pci-e slots my case is a bit of a mess. Anyway, not that it matters but i have doubts as to whether the back of the 5970 acts as an intake. If you look at the 6990 with the exact same fan but center mounted it is designed to suck air into the middle of the card and blow air out the card in both directions. If you have a fan mounted at the end of the card as in the pic from RECON-UK, in an attempt to blow air into the back of the card it will probably just be competing with the air exiting the back of the card. I am not sure why those vents are there. Take a look at the 6970 and it has the same fan setup as the 5970 and the there are no vents. The only air intake is through the fan. If you are brave, while you are running a game or stress test take a playing card or something similar and cover the fan hole and not the vents at the end of the card while keeping your hand at the rear vent and feel how little airflow there is. If you have air flow from the bottom of your case and a clear path to the fan intake on the card just mount a 120mm fan on the bottom of your case pointing upwards towards the fan hole of the card. This will help keep temps down.
  16. ^^ I realize that may be the case but if so I feel like that is a little bit poorly designed. The location of a graphics card in the case is roughly on the same level as the case intake fans. And being that the 5970 is so long, in most all cases the rear of the card is going to be only a few inches from the intake fans pulling air into the case. Why would they design the card to throw air right back out into the intake fans?

    If this is in fact the way it is designed that seems to me to completely go against common sense of case cooling. It would not be keeping the case air flow one directional. As hot as these cards can get, why would they design them to blow hot air right back into the case?
  17. Dude, your gpu is not blowing hot air back into your case. IMO the vents at the far right are pointless. I have read reviews that say those are air intakes but that fan blows air in all directions in a 360 degree pattern. How could it possibly suck air in those vents when immediately to the left of the vents is a fan that blows air in all directions was my point. Anyway, the two gpu's and the heatsinks are all located to the left of the fan which is pushing air over them and out the left side of the card. In regards to your quesiton about the intake fans, if you take the fan and point it in the other direction it is now an exhaust fan not an intake fan. With my 6990 the center mount fan blows air to the left and right over each gpu which it is in between. The left gpu has it's hot air blown out of the case and the right gpu has it's hot air blown directly into my case and I have a 120mm fan seated immediately to the right of the card and the fan is pointed to exhaust the air out of the case. The reason behind the center mount fan is because these two gpu's in the 6990 get f$%king hot and if the fan was mounted similar to the 5970 it would blow already hot air from the first gpu over the heatsink of the second gpu and it would always run hotter the the first gpu. Have a look at the 6970. It has the same configuration as the 5970(with only gpu) and there are no vents to the right of the fan.
  18. The best stress test for a gpu is to play a game. My 6970 and 6990(the 6990 is basically crossfire 6970's on the same card) are designed to run at 80 degrees under load. This is the same while playing bf3 or running 3dmark11. If you are running low 70's playing bf3 then that is about as hot as it will get.
  19. Have a look at the pic midway down the page

    i know it is a different card altogether but the setup is still the same and I beleive this is where Nvidia started copying AMD. It shows the fan and immediately to the left is the heatsink on the gpu. The fan blows in all directions with no discrimination.
  20. The fan is a blower and the case is what picks the direction it blows in. The blower on a 6990 has 2 ends open and thereby blows air out both ends.

    In the OP's 5970, the blower case only allows air to go one way, but the bottom of the blower has some holes. The holes allow some air in as well as allow proper fitting of the caps and voltage system that sit too high.

    Image from Anandtech with some blue lines for approximate air guide(shroud) location
    Blowers are generally used in 1 direction air pulls in either side(mostly from the front, but on some blower air comes in on both sides). If it did not have the guide(shroud), it would not push very much air at all.
  21. Ok. I can understand that. Now I've got another question. If the fan is placed at the back of the card such as on the 5970, and it does blow in all directions, what component is being cooled at the back? There is nothing back there. All the GPUs, heatsinks, vrams etc. are all back to the left of the fan. Why blow air to the right at all?
  22. It does not blow in the back at all.

    The shroud prevents this, a very small amount of air is actually pulled from the back vents because there are some openings on the bottom of the blower.

    Here are some very good images of the heatsink taken apart. You will see the shroud that makes the air travel in one direction as well as a few holes that will allow some very small amounts of air into the blower from the underside. It is a very small amount and does not add to overall cooling.

    Still have questions? I will try to draw some air lines for you. just ask...
  23. Hmm. Interesting. I just picture the 'blower' blowing air towards the vent holes at the right side of the card. The only difference I see from the air flow in the 6990 aside from a shorter distance for the air on the right to travel to exit the case are the small angled fins just in front of the vents on the 5970. I know on the 6990 the air flows equally out the left and right side of the card. So those little fins redirect all of the air from the blower that would normally exit the right side of the card to the left side of the card? I'd like to see some wind tunnel tests with this setup.
  24. So just take a small piece of paper and start up your favourite game and hold it in front of the vents and see what happens. I guess it makes sense that the air gets redirected through marvels of airlflow engineering to suck from the right and blow to the left but I failed to read in the review where it says the right side vents suck air in. It does talk about a small amount of hot air venting into the computer case from the card through all the holes in the cards case.
  25. The air that vents into the case is at near the exhaust of the card, this is because, the small vent on a 5870 simply can not take all the air flow so they vent some near the end of the card.

    If you look up at the first pic i posted, you can see this guide to send some air into the case.

    or this maybe, its a 5770, so its not the same, but the vent locations are the same

    The 5770 takes much more air into the back vents then the 5870 or 5970 because its voltage system in in that location and is cooled by the air flow. The higher end cards are cooled by a metal plate heatsink.

    For a standard PC blower the flow is like this.
    The air moves around the guide with no place to escape until it hits the one and only place it may leave by

    For something like your center fan there would be 2 openings in the guide
    Don't mind the mspaint image
  26. Just when you think you know it all....
  27. Next time you open your furnace to clean it(and i hope you do), you will see a big blower(most likely open on both sides with one outlet to take in and move more air). The idea of blowers has not chanced at all over the years(If you work on cars, you will find them as well). They are very good for high static pressure air(they can push through anything even a tight packed heatsink).

    No one will ever know it all :)
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