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Same temps regardless of fan speed?

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J So

Member
Joined
Sep 26, 2004
Location
Sacramento, CA
I got sick of having 3 120mm fans going full blast six inches from my head while trying to sleep so I decided to get a fan controller. I hooked it up to one of the fans on my shroud while leaving the bottom 120 blowing full speed onto my 6800 gt, one to the 80mm fan cooling my hard drives and the final to the 120 exhaust fan I have. It did cut down on the noise and it makes it easier for me to sleep now but I have noticed something strange.

When I have the fans turned all the way down my GPU core is exactly the same as when I have it set to maximum and my CPU goes up a whole 1 degree celsius at full load! I tested this by running rthdrbl for about 15 min until my temps peaked then turned up the three extra fans and waited 4 min to watch my GPU temp drop by 1 degree.

What's up? Is this normal? Could this be becuase I have a decent sized shroud and the 1 fan at max and the second at low are pulling all that's needed to cool my system? I wonder if we don't need that much air and would be able to get by with a nice single 120 Sanyo Denki with a fairly large venturi shroud..

Anyway this is what my core and shroud look like

shroud.jpg
 
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you probably reached the peak of your dissipation, try lowering both fans on the rad to make it more efficient.
btw, i'm liking ur shroud
 
There comes a point where more airflow won't get you better preformace, even on air cooled systems. Its obvious you have reached that point on your watercooling setup. :clap:
 
Nice! this is what I figured but I wanted to be 100% sure!

Thanks Korndog all my semi-geek friends are in awe of it.. lol I must have heard "you're crazy" 30 times on the day of my build from my roomate and his friends.
 
that's exactly what's happening with my setup, one 120mm fan on a heatercore. i keep the fan at the lowest voltage possible (it's barely spinning = no noise at all) and if i crank it up to full 12V the temps do not change at all.
 
2Busy said:
Second that on the shroud. Excellent work. Did you saw your cuts with a saw or what?

I used a table saw with a fine toothed blade. For the holes to the fan I used a dremel but it was a huge pita becuase the cutting wheels I had were barley larger than the 1/4 plexi I used on the shroud so I pretty much had to cut from the top and then the bottom to clear.

I got my supplies at Tap Plastics and they were WONDERFUL on helping me pick out what I needed. I bought thier in house brand of solvent cement with the applicator and it worked just as they said it would.
 
For my solvent welding I just use a seringe with a tapered end and some MEK I got from Home Depot. I am looking for a local supplier of PlexiGlass soon. Got to get some plexiglass shaped like a cylinder to make my odd-ball T line out of.
 
funny, I just went to radioshack and got me a rheostat and I turned it down, My temps droped a whole 1C sometimes not even a C, and I thought my temp Sensor was being stupid like it usally is.
 
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