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Other => CPU/GPU Bitcoin mining hardware => Topic started by: mackminer on July 30, 2011, 05:31:33 PM



Title: Opinions on blowing air directly onto 6990's
Post by: mackminer on July 30, 2011, 05:31:33 PM
Hi,
I have 3x6990's in a haf x case in which the side fan facing the cards is not powerful enough. I am thinking of replacing it with something like this... Would it be ok to blow air at this force onto the cards?

Thanks.


Title: Re: Opinions on blowing air directly onto 6990's
Post by: pbj sammich on July 30, 2011, 06:58:32 PM
you didn't actually link anything.....

Assuming it's a fan, if so yes

I have one pointed at mine and works well ~10C drop


Title: Re: Opinions on blowing air directly onto 6990's
Post by: mackminer on July 30, 2011, 07:44:23 PM
Sorry, but it would be about 250cfm.


Title: Re: Opinions on blowing air directly onto 6990's
Post by: CanaryInTheMine on July 30, 2011, 11:56:21 PM
I have 2 6990 in one rig and am using 450 cfms blowing directly on them from top.  i leave fans on auto with this... runs quieter than setting 6990 fans to a higher constant rate.


Title: Re: Opinions on blowing air directly onto 6990's
Post by: Jack of Diamonds on July 31, 2011, 12:33:16 AM
I run cards in a dedicated place with ventilation so just default fans..

If you run these at home you will *need* extra fans blowing air on the cards if you want to actually live in the house.
(Well.. Even if you put them in a basement, many cards next to one another will still run very hot)

The fan noise of these cards at 100% is absolutely unbearable.
Actually measured ~85dB with a professional Extech decibel tester a few meters away, which is not that far away from a small jet engine.

Anyway, if you want to cool a ton of rigs at once, try these. They are very power efficient for the amount of CFM provided.
http://i56.tinypic.com/kds5l1.jpg

http://www.seabreeze.ca/fans/TurboAire/turboaire.html

Home Depot, Costco and some other big retailers routinely carry these in their inventory.


Title: Re: Opinions on blowing air directly onto 6990's
Post by: Tx2000 on July 31, 2011, 01:32:24 AM
@Jack

Do you know the dba on that fan?  Curious as I might pick one up.


Title: Re: Opinions on blowing air directly onto 6990's
Post by: Jack of Diamonds on July 31, 2011, 02:49:25 AM
Their specs don't list precise dB numbers, but it promises 'whisper quiet' on all speeds. A retailer near you might have a sample piece to try out.

To my ear it sounded maybe ~20dB on high, not whisper quiet but definitely something that wouldn't disturb your sleep. Magnitudes quieter than the 6990 fan on 50%.