Hardwire fan

Hiao,

I'm adding another fan to my laptop, what I need to know at this point, I want to hardwire the one fan I'm adding to the 'heatsink'. Those are same, I just swapped out my heatsink and therfore have another fan. I have the room for it, but I wonder how it will do if I hardwire those two together.

Anyone actually tried this?

 

Fan controller circuitry may not be able to handle both. The safest way is to hardwire it to a USB power rail (5V, it is compatible). The bad thing is that the new fan will run at full power...


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The PWM signal is not very strong, it's just a small voltage hooked up to the fan. However I still think you should be able to run it in parallel since it's only switching a transistor.

The only time current draw might be a problem is when the fans go from 0 to full instantly. That's when they draw the most power. If they're slowly revving up they draw much less current. Fan controller circuitry is quite basic and designed for larger loads already, so I think you'll be safe. If the controller can only supply a certain amount of current, the fans will run slightly slower (but still you'd move more air overall).

Tapping off the USB will make the fans run all the time, even when the computer is off sometimes (if your computer has a powered USB mode or if USB is powered during standby).

One other consideration: not sure how you plan to do this but if you have two fans with airflow in series (ie: one fan blows into the next) both fans will run faster than normal and it puts extra strain on the bearings. They will both wear out faster. So see if you can arrange it so the fans that blow separately.

 

Thank you both. USB power is out of the question as I'm using this laptop all over the place wich sometimes requires it to be quite.

Yes, they have both their own direction. The thing is, I've modifed my underpanel, and have a tempratures of mid-20Cs of idle temprature on CPU. But, when I run OTHEROS, the problem isin't the CPU or GPU. It is the Chipset. This fan is right above my CPU socket and since the Chipset is right beside, it is covering both while the heatsink takes care of GPU and the heat from CPU thorugh heatpipe.

My fans goes to 0 at 25C. And does start spinning again around 30Cs. They never go from 0 to maximum. I disconnected my heatink fan, and did startup my laptop with only the additional fan I added, I were able to startup, listen to music, basically do the most basic tasks without overheating...

What do you think, should I just go for it and try out?

 

I'd love to see pictures

 

How about this: Connect the power lines (red and black wires) to a USB rail. It will get 5V from there without loading the original fan power rail.

In the mean time connect the fan rpm controller wire (pwm - yellow wire) to the original fan's socket. The pwm signal will adjust both fan's rpm's. This should work pretty well in theory.


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Yes. In theory. The only problem here is that, the cable is extremely short. So, my both fans are actually right beside eachother, just pointing two diffrent directions. However, I think I'll try both to in one first, and then see how it turns out. If not, I have to make longer cables, and them to a USB rail.

Just another question about USB, I have actually never done that, but does the USB port get unusable? Or, can I still use my USB port with my External HDD or my flashdrives?

Ah, about the picutres, my laptop does look like a mess now, but maybe I upload some finished product in the owners therad

http://forum.notebookreview.com/acer/588074-official-acer-aspire-5739g-owners-lounge.html

 

No, it won't get unusable. You will not touch the data rails of the USB. However since the total amp is limited you will not be able to withdraw as much current as before from that USB port. Flashdrives should still function normally but you may need to use other USB ports for the external HDD (if it withdraws the current from the USB, not from an external adapter).


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okay, it did work actually. And my both fans does actually run at full speed under full load. Amazing? My lowest temprature is still 24C as my fans quit at 25C just as before. I'm running Otheros now, to see how it does under full load. Chipset did always reach 100C, going to see if this actually helps or not now.

UPDATE:

Okay, my Chipset peaks at 94C after 5 minutes with CPU torture with OTHEROS. The thing is, the fans does not run at fullspeed untill 90C. Bad bad bad. And they set back again at 85C. I think this is the reason why my laptop shuts down with one fan. Impossible to handle the heat after going full speed at 90C. Allready too late. Also, my CPU is at 76C.. The temprature on chipset is somewhere between 80-85C and CPU 60-70C.

UPDATE2:

Everything is actually working great! I've removed the second fan however, the reason is that I need to find another spot for it. CPU idle temprature got low as 22C but the problem is that with fan I have to raise my whole laptop.. And that is just ugly.

 

IF its a FINE BOOTY then it might be attractive you never know
Also Id like some pics