Totally fanless AAO A150-BGb with SSD = 0 dB

Since december 2008 I have had an Acer Aspire One A150-BGb (Windows XP, 160 GB HDD, 3G adapter, etc.). It has served me extremely well, especially at work. However, a while back I lost my tolerance for noisy computers and made the netbook dead silent by completely eliminating the fan and swapping the HDD with an SSD. Details of the project - which I chose to call The STFU Project since I had literally started to hate :evil: the noisy fan and to a smaller degree the HDD - can be found at Flickr:

http://www.flickr.com/photos/murre-x/sets/72157622898633201/

It's not a step by step instruction though, and perhaps there's a better way, but so far the machine is just wonderful and works flawlessly.

Any questions and suggestions are welcome. :geek:

 

Nice Mod Mate !
Congratulation.

I love that mod, especially the fanless idea.
some suggestion:
1.You could try to get a cooper heatsink, a custom made one.
The cooper will take the heat better as the aluminium. the aluminium dissipate the heat better.
2.another ideea is to use a peltier element. I"m not an expert with this things, but i saw some projekts.
3.what about the ideea to use the laptop case for heat dissipation ?
in that case you will need a conection between the heatsink and the case. the case shoul also be metalic...

this are just some thoughts, maybe there will be somebody who can do something like that.

Respect again for your work !

 

Hey Murre X, first off, very nice guide on all of this. I was pondering on how to do this just this morning, as i knew that if you unplugged the fan the laptop would not last but less than a minute. So that being the case, I am still needing help on how to "trick" the PC into thinking a fan is plugged in. I understand what you are saying about the Hz and all, but I do NOT know what i need and how to wire it in order to properly trick it into running without a fan. I have copper heatsinks ready to go and the SSD is coming for Christmas, just needing a bit of help with this. Thanks,

Richard

 

Hi radu14m,

Thank you for your appreciation and suggestions! Copper heatsinks would be great I think, perhaps connected via heatpipes to a light metal plate under the whole netbook.


Hey Richard,

My 555 circuit consists of the following components soldered to a piece of prototyping board:

1 x 555 timer IC (Texas Instruments SA555P)
1 x 4,7 kohm resistor (R1)
1 x 1,0 kohm resistor (R2)
1 x 1 uF capacitor (C1)
1 x 68 nF capacitor (C2)
3 x Isolated wire (black, red and yellow)
5 x Isolated solid copper wire (red)

I buy my electronic stuff at ELFA.se (no affiliation). For example, the prototyping board's stock number is 48-326-14, and the 555 timer IC's 73-041-17.

I've added a closeup photo and a schematic of the 555 circuit to my flickr page:

http://www.flickr.com/photos/murre-x/sets/72157622898633201/

That is of course only one of many ways to organize the circuit. I'm sure there are better ways. (Perhaps when I have more time I'll etch a PCB.)

I would start by trying out the circuit on a solderless board.

As can be seen in the pictures:

- C1 (blue) connects pins 1 and 2 (since electrolyte, negative leg goes to pin 1 i.e. ground).
- C2 (red block) connects pins 1 and 5 with the help of a solid copper wire (red).
- R1 (black, 4K7) connects pins 7 and 8.
- R2 (black, 1K0) connects pins 6 and 7.
- Pins 2 and 6 are shorted with the help of 2 solid copper wires (red).
- Pins 4 and 8 are shorted with the help of 2 solid copper wires (red).
- Black wire (ground voltage) is connected to pin 1.
- Red wire (supply voltage) is connected to pin 4 (or 8).
- Yellow wire (signal voltage) is connected to pin 3.

The A150's fan connector has three wires: black, grey and brown. The black is ground, the grey is supply, and the brown is signal. My 555 circuit also has three wires. I chose black for ground, red for supply, and yellow for signal. Thus, separate (rip or cut) the fan from its wires as close to the fan as possible, and connect (solder or wind, and isolate with electrical tape) each wire to its corresponding wire from the 555 circuit: black to black, grey to red, brown to yellow. Or, you can simply solder the fan wires directly to the 555 circuit board: black to pin 1, grey to pin 4 (or 8), and brown to pin 3.

The frequency of the signal generated by the 555 circuit, is determined by R1, R2 and C1:

f ~ 1.443 / (R1 + 2*R2) / C1

Using the values in the list of components:

f ~ 1.443 / (4700 + 2*1000) / 0.000001 ~ 215 Hz

Note however that although the measured (multimeter) values of R1 and R2 were spot on, the value of C1 was 1.166 uF, which according to the above formula should give a frequency of about 185 Hz. That was also the frequency I measured from the final 555 circuit and happened to be aiming for, but 215 Hz would have worked as well. In fact, while testing the circuit on a solderless board with potentiometers, I was able to keep the computer going at a frequency as low as 60 Hz and as high as 400 Hz. In hindsight I should have tried to determine the lowest possible working frequency, but I was too eager to finish the project and continue using my netbook. I just assumed the shutdown was caused by an instruction of the form: "if f < fmin then off" where fmin < 60 Hz, and thus that 185 Hz was more than a safe frequency in the final circuit.

The capacitor C2 is for improved operation, as recommended by the specification for the particular 555 timer IC I decided to use: Texas Instruments SA555P. It does not have to be 68 nF. 10-100 nF should work. Using an old 555 timer IC I happened to have around, I didn't need C2 while experimenting on a solderless board. When I soldered the permanent circuit, I decided to use the Texas Instrument 555 timer IC because of its specified temperature range: -40 C to +85 C.

The board rests on double tape over rubber foam, to make it stay put and isolated from the A150's motherboard.

Sorry if I was over-explicit.

Murre

 

Dear MurreX,

I am wondering if it would be possible for you to answer some questions?

1) What temperature does your fanless netbook output when it is using the heatsinks? What response do you get when using programs such as A1CTL?

2) Would it be possible to use smaller heatsinks so as not to cut a hole in the bottom of the netbook? Would it still function correctly?

3) I am wondering if it would be possible for you to recommend any heatsinks?

4) Is it necessary to use a Texas Instruments 555 timer or will any 555 timer be acceptable?

Any information would be greatly appreciated.

Thank you for your time.