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View Full Version : 20C load temp diff in 4890 CF !?

King107s
03-13-10, 03:18 PM
I have two 4890's in cross fire and I was playing Crysis for a couple hours and when I came out of the game and went to CCC to turn the fans back down I noticed that card #1 was 75C and card #2 was 55C is this normal? The #1 card is normally a few degrees hotter at all times like 55C vs 50C but I wasn't expecting this...
sandyduff
03-13-10, 04:13 PM
Is the hot card the one on top? Might be restricted airflow due to crossfire....
King107s
03-14-10, 08:52 AM
It is the one on top... I thought the side fan was going to help with that but I guess not enough. Do you think 75C load is too high? This is the over clocked 4890 model (http://www1.sapphiretech.com/us/products/products_overview.php?gpid=307)

BTW Idel temps are 51C and 42C
Neural Net
03-14-10, 02:19 PM
It is the one on top... I thought the side fan was going to help with that but I guess not enough. Do you think 75C load is too high? This is the over clocked 4890 model (http://www1.sapphiretech.com/us/products/products_overview.php?gpid=307)

BTW Idel temps are 51C and 42C

75 is fine, no need to worry. One idea may be to put a 80-120mm fan on top of the 4890 where the GPU is placed, this will reduce temps by about 10 degrees or so, but it will slightly increase your CPU temperature.
Rattle
03-14-10, 02:34 PM
turn the fan on the top card up about 5-10% more than the bottum one, temps will even out.
baris_
03-14-10, 02:50 PM
What about switching the cards. Maybe your top one just runs hotter than the other one and putting it in the place where it's likely to get even hotter (on top) might enhance that difference. Just try it out, theres no harm in that.
King107s
03-14-10, 04:06 PM
75 is fine, no need to worry. One idea may be to put a 80-120mm fan on top of the 4890 where the GPU is placed, this will reduce temps by about 10 degrees or so, but it will slightly increase your CPU temperature.

I'm water cooling so it wont make much of a difference on the cpu temp. I took another look at the space between the cards and it looks more than sufficent for airflow IMHO. See the pictures below.

turn the fan on the top card up about 5-10% more than the bottum one, temps will even out.

When I'm gaming I turn both fans to 100% and put the head phones on. So that idea wont work here :(

What about switching the cards. Maybe your top one just runs hotter than the other one and putting it in the place where it's likely to get even hotter (on top) might enhance that difference. Just try it out, theres no harm in that.

I could try that and I just might out of curiosity...

Here are som pics of my set up:

http://i2.photobucket.com/albums/y5/king107s/computer/IMG_0893s.jpg

http://i2.photobucket.com/albums/y5/king107s/computer/IMG_0894s.jpg

http://i2.photobucket.com/albums/y5/king107s/computer/IMG_0895s.jpg

http://i2.photobucket.com/albums/y5/king107s/computer/IMG_0897s.jpg
baris_
03-14-10, 04:13 PM
That looks quite messy to be honest. I think you'll already get a temperature decrease if you could make it less messy. IF possible of course.
King107s
03-14-10, 04:22 PM
Well, I dont think the picture does the cable management much justice. I have zip-tied and routed the cables as well as I could. I'm getting about 34C to 39C across the 4 cpu cores at Idle and no more than 55C after 18+ hours of full load which I dont think would be possible with bad airflow through the case. IMO
Rattle
03-14-10, 04:26 PM
not sure why you need 100%

someone mentioned one card may run hotter. having run 4870 and 4890 cf i would test each card and one would usually run 5-7c hotter. With 900/1000 clocks on both card I ran one fan 40% and top fan 50% hotter card on the bottum and temps both leveled off at 65c or so. My cards were reference though, i do not like 3rd party cooling solutions aside from vapor x on my ATI cards.
King107s
03-14-10, 04:30 PM
not sure why you need 100%

someone mentioned one card may run hotter. having run 4870 and 4890 cf i would test each card and one would usually run 5-7c hotter. With 900/1000 clocks on both card I ran one fan 40% and top fan 50% hotter card on the bottum and temps both leveled off at 65c or so. My cards were reference though, i do not like 3rd party cooling solutions aside from vapor x on my ATI cards.

I probably don't need more than 60% but oh well theres a lot of things about overclockers that tend to go in the direction of excess wouldn't you say? I used to have a 4870/4890 CF set up as well before I got a second 4890.
Neural Net
03-14-10, 04:36 PM
I'm water cooling so it wont make much of a difference on the cpu temp. I took another look at the space between the cards and it looks more than sufficent for airflow IMHO. See the pictures below.


Definitely enough space there. Give it a shot, it's a quick and easy solution, a fan can just rest on top of the card and push air away from it. I did this with my 4870 X2 as the GPUs were in a line, the one closest to the fan's exhaust would get a double dose of heat output and would overheat with early drivers. Your hotter 4890 might just in a dead zone in terms of airflow.
Austin3334
03-14-10, 04:55 PM
you could try a pci slot fan to exhaust the air under it out or get one the just blows straight up.

Any of these should help. (lian li looks like the best, you can make them exhaust or suck in)
http://www.newegg.com/Product/Product.aspx?Item=N82E16811995026
http://www.newegg.com/Product/Product.aspx?Item=N82E16811995024
http://www.newegg.com/Product/Product.aspx?Item=N82E16835119065
http://www.newegg.com/Product/Product.aspx?Item=N82E16835114024
NOVAA
03-14-10, 10:00 PM
Stick your hand in the case while its running a game and feel the air around the back of the bottom card. Its a good 20C above ambient, probably more. Thats what the top card gets to use for its cooling. Totally normal don't worry, what I want to know is how you get your bottom card to run so low under load? 55C? Mine run at about 80C in Crysis, and I only have one! What are your fan settings like?

And yeah like someone said, probably just turn the fan up on the top one a bit and it'll go down a bit, but 75C isn't anything to worry about so don't freak too much.

Edit- Didn't see you game with fans at 100%, nvm lol I see how you run them so cool and don't worry about your top card, 75C is fine.
King107s
03-15-10, 02:30 PM
Stick your hand in the case while its running a game and feel the air around the back of the bottom card. Its a good 20C above ambient, probably more. Thats what the top card gets to use for its cooling. Totally normal don't worry, what I want to know is how you get your bottom card to run so low under load? 55C? Mine run at about 80C in Crysis, and I only have one! What are your fan settings like?

And yeah like someone said, probably just turn the fan up on the top one a bit and it'll go down a bit, but 75C isn't anything to worry about so don't freak too much.

Edit- Didn't see you game with fans at 100%, nvm lol I see how you run them so cool and don't worry about your top card, 75C is fine.

I think others have hit the mark by pointing out that the top card is using hot air surrounding the second card to try to cool off with...

I also understand that ATI CrossfireX is supposed to split the rendering tasks using Supertiling so that the work load is better balanced across the cards but I always felt like the first card was doing more 'work' than the second one as it is the primary card. I liken it to core 0 of a quad core, its always doing more work than the other cores. I could be wrong though, I havent done my research here yet.