Project:Passive cooled pc

From London Hackspace Wiki
Revision as of 23:51, 23 March 2012 by Daveb (talk | contribs) (some maths advice)
Jump to navigation Jump to search

Intro

It's forever bothered me how much noise desktops make. Fans just seem to blow the air round and round and the general setup seems poor.

The Idea

Design and hack together a better setup, with large heat sinks on the exterior and heat pipes to move the heat energy away from the hot bits. Plan is to engineer to the worst case scenario of hot, high end CPU and GPU running on a warm day.

Inspitation

Review with pictures of Zalman TNN-300 Fanless PC Enclosure

Step by step to make a heatpipe based cooling system (SilentMods)

The Challenge

Did some noise testing on my machine, taking out the different parts and measuring noise levels, here's the results:

Totally off (just background noise):: 34 dB
Everything on, idle cpu/graphics: 56 dB
No GPU: 46 dB
No GPU & No HDDs (3): 42 dB
No GPU & No HDDs & No CPU fan: 37 dB


Meaning each component makes roughly this much noise:

PSU Fan: 3 dB
HDDs: 4 dB
GPU fan: 10 dB
CPU fan: 5 dB


'dB' is an exponential scale, so you need to convert the dB values to a linear energy scale before you can add or subtract them..
In a spreadsheet, if the dB value is in cell B2, '=EXP(B2/10*LN(10))' is the sound energy.
The dB value from a sound energy in C8 is '=LOG(C8)*10'.


PSU Fan: 34dB
HDDs: 44dB
GPU fan: 55dB
CPU fan: 40dB

For reference:

0 dB Threshold of hearing
30 dB quiet bedroom at night
60 dB conversational speech 1m away
80 dB beside a busy road


Design


Materials

Heatpipes

8mm x 300mm heatpipe via Farnell £10.38 each

ZM-2HC2.jpg

ZALMAN NP Heatpipe HDD Cooler - contains 11 (6mm x 150mm) salvageable heatpipes amazon £13.50

Heatsinks

Heatsink1.jpg

Dimentions: 300 x 345 x 25mm

eBay £16.00