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Other => CPU/GPU Bitcoin mining hardware => Topic started by: zard_cz on July 23, 2011, 07:37:38 PM



Title: 6870 exhaust "mod"
Post by: zard_cz on July 23, 2011, 07:37:38 PM
Hi,
I have the XFX 6870, the reference version with the single intake in the back of the card, however, the exhaust is split into two parts, one of them points out of the case but the other blows the air in. I was not really happy with the extra hot air getting back into my case, so I have taped over it.
Looking at the disassembly pictures it looks as a single stream of air divided between those two exhausts, could there be any problem with this? The temps are 65C incl. overclock and fan running on 40-50%.

Anything I should be worried about?


Title: Re: 6870 exhaust "mod"
Post by: vapourminer on July 23, 2011, 10:12:47 PM
without pics of the card minus the HSF assembly its hard to tell, but I would be worried about the VRMs not getting airflow. they are typically near the PCIe power connectors and that path is what it sounds like you are blocking.

can you monitor VRM temps?


Title: Re: 6870 exhaust "mod"
Post by: zard_cz on July 24, 2011, 01:03:38 AM
No, I don't think I can. This picture made me think it's probably ok:

http://www.overclockersclub.com/reviews/amd_6800series/images/31.htm

(it's upside down) - you can see that the air is just being diverted out and inside to the case. I am just blocking the inside of the case.


Title: Re: 6870 exhaust "mod"
Post by: Detritus on July 24, 2011, 04:33:54 AM
Hi,
I have the XFX 6870, the reference version with the single intake in the back of the card, however, the exhaust is split into two parts, one of them points out of the case but the other blows the air in. I was not really happy with the extra hot air getting back into my case, so I have taped over it.
Looking at the disassembly pictures it looks as a single stream of air divided between those two exhausts, could there be any problem with this? The temps are 65C incl. overclock and fan running on 40-50%.

Anything I should be worried about?

I don't think it'  a problem. I have messed around with doing this on my cards as well, and haven't found it a problem. The temps are good.

One thing though, all the XFX cards have the XFX logo stamped into cutouts on the exhaust port on the plate. IT looks pretty restrictive to me. I'm tempted to get the dremel out and open the exhaust port up all the way and see if it helps temps. I bet it lowers the noise a bit too, less turbulence of the exhaust air.


Title: Re: 6870 exhaust "mod"
Post by: cicada on July 24, 2011, 05:07:29 PM
One thing though, all the XFX cards have the XFX logo stamped into cutouts on the exhaust port on the plate. IT looks pretty restrictive to me. I'm tempted to get the dremel out and open the exhaust port up all the way and see if it helps temps. I bet it lowers the noise a bit too, less turbulence of the exhaust air.

It's this regular-style exhuast:
http://dl.dropbox.com/u/15821147/mining/hisbackpanel.jpg

Versus XFX's exhaust:
http://dl.dropbox.com/u/15821147/mining/xfxbackpanel.jpg

It's hard to say which is more restrictive..  chopping off the logo or the fins is definitely going to hurt resell value if you've ever got that intention ;)


Title: Re: 6870 exhaust "mod"
Post by: Detritus on July 24, 2011, 10:12:56 PM

It's hard to say which is more restrictive..  chopping off the logo or the fins is definitely going to hurt resell value if you've ever got that intention ;)


Yeah, I know. But by the time I'm done mining with these cards they will probably worth about $20. :)


Title: Re: 6870 exhaust "mod"
Post by: Sannyasi on July 24, 2011, 10:17:25 PM
i chopped off all the fins on a 5870- i can feel the difference in air movement with my hand but i didn't think to check before temps so nothing to compare to- i do think it makes a difference though