Green PC Challenge

Ecological issues around computing. This is an experimental forum.

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rubber_boat
Posts: 14
Joined: Thu Nov 15, 2007 3:59 pm

Green PC Challenge

Post by rubber_boat » Mon Jun 23, 2008 11:38 am

I want to underclock my video card, to reduce the heat output and lower the power draw. Any help on the video card, or further setting up the CPU is appreciated. Or any tips.

Electricity consumption is a primary concern. The other concerns are heat and noise. Electricity is 20 cents per kilowatt hour, although it's all produced from wind and solar.

The video card usually runs around 67 deg C now, after the overall case temperature has been reduced by underclocking the CPU recently, and adding a Papst 60mm fan for exhaust (model 612F I think). The fan is manually slowed by a Sunbeamtech's Superior 20-in-1 front panel module, since the MB fan control of the Shuttle AN35 was not connected by Shuttle (any idea how to fix that?). I also want to generally cut down on the noise and idle heat output. I guess I have no life, but I also have no money and probably too much time on my hands.

Athlon XP 2600+, Barton core, week 0347
Shuttle AN35 Ultra v1.1
Nvidia 6600GT
Silent Green Giant 80Plus PS from LC
Fujitsu-Siemens Scenic-L case

The defaults, which I ran for months:
1.65v at 1909 Mhz, 166Mhz FSB
seems high and according to spec is 52.3 watts.
It's running now at 1.250Vcore and 1035Mhz, 16.7 watts, with Prime95 reporting no errors for about 30 minutes.

The box is sits in a cabinet. The way these old Berlin buildings are mostly constructed, the kitchen has an old cabinet, built into the wall underneath the kitchen window, between the breakfast nook and food closet. There, the outside wall is thin, and this cabinet would have been the place to store cool or cold items in the winter. It's about 30% higher inside the cabinet than the height of the FS case, leaving room for a shelf with the Fritz!Box 7050. I've got a digital thermometer and clock on the shelf, near the FB and above the heat exhaust (PS) of the FS case. Readings vary from 28 to 40 C, depending on day or night, and whether the sun is shining into the hof, directly heating the other side of the cabinet wall. The cabinet was insulated some time ago with styrofoam, but not the back wall. Doing so keeps the cold during the winter inside the cabinet and away from the kitchen. It also ended up conveniently keeping the sound and heat from the kitchen in the summer, when we decided to move the equipment in there.

Adding to the proof I have no life and too much time, I made a chart of the CPU during one of the beautiful blue-sky days. I've attached it here. It's made with OpenOffice Calc. You can put in different values and it calculates the cost of running, or savings, or moves the points on the graph.

I have a question also about Radiate. Attached is the custom profile I made for the CPU. If I keep voltage to the processor constant, and increase the frequency a bit, why does the watts consumed go up? Maybe I don't understand enough about CPU architecture.

I have Speedfan 4.34, 8rdavcore 0.8.8 dev8 which has specific support for the shuttle an35 ultra v1.1, prime95 to test the CPU.

What is the readout on Speedfan for the CPU? I guessed it was the second temp readout of the IT8712F?? I can't seem to find documentation anywhere on what temp readouts correspond to which areas of the board.

http://pettenkofer.dyndns.org/offentlic ... ents-1.rar
Picture of the cabinet setup
Screenshot of the administrator session, including speedfan, 8rdavcore, and prime95
Spreadsheet with chart

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