Acer Aspire 5730Z bypass PWM fan requirement?

[Per Hansson]

Hi, I'm upgrading a friends Aspire 5730Z laptop with Win7 x64 & a Seagate SSHD.
It's a super ghetto mod because the asshats that she turned it in to at first threw away the original HDD including caddy!

Anyway, laptop is working great now but there is always a "but"
The fan was really close to failing and sounded like crap, so I ghetto modded a nice Sunon fan so it would fit, but was stupid enough not to see if it would spin first.

And as it turns out it does not, it just makes small jerky movements back and forth when connected. (It runs fine if connected to a normal +5v source).
The old fan is just a normal 3-wire fan, but after I took it apart I found a LV8800 PWM IC...
(Up untill now I thought all PWM fans where 4-wire fans, learn something new every day!)

So what I'm asking is if there's some way I can get the Sunon fan to run with the PWM signal? (I don't wanna ghetto mod it by connecting directly to another 5v source).

[Per Hansson]

Re: Acer Aspire 5730Z bypass PWM fan requirement?

Hahaha, I found the reason it will not spin now
There is a speaker magnet below the fan that messes with it!
Move the fan out of the magnets way and it spins just fine!
Now I just gotta find some way to shield off the magnet...

[ben7]

Re: Acer Aspire 5730Z bypass PWM fan requirement?

You can get metal sheets designed just for magnetic shielding. You occasionally see this stuff on large iron core power transformers. I think one product is called "mu-metal", however there has got to be others out there...

LOL at the fact that the speaker magnet was messing with the fan ... EPIC fail!

[Per Hansson]

Re: Acer Aspire 5730Z bypass PWM fan requirement?

I think one product is called "mu-metal", however there has got to be others out there...

After finishing a Fullers Indiana Pale Ale something dawned on me:
I took a sledgehammer and flattened it's bottle cap:



Then some duct tape and super glue:



Presto working!!!



Yeah baby, that's some real redneck modding for ya
Please do note the USB cable which has been taped to the HDD, replacing the original HDD caddy.
Along with some foam underneath the 7mm HDD to make it fit into the 9mm housing

[dj_ricoh]

Re: Acer Aspire 5730Z bypass PWM fan requirement?

this is a very awesome post ! good for you. GJ!!

[Per Hansson]

Re: Acer Aspire 5730Z bypass PWM fan requirement?

Thanks
If it where not for the fact that this was such a fun project I would have just told her to buy a new laptop.

I thought that the "PWM signal" would be killed by a capacitor, that's how I found out:
I put a capacitor between 5v and ground to smooth the voltage out, and then the fan started.
I removed the cap and it still ran, so I put the fan back into the correct position and could see & hear it slow down from the magnetism!
I literally laughed out loud when I realized what it actually was!


Another fun fact to the quote below is that the original fan probably failed due to the magnet.
Because it was pulling on the motors axle making it unbalanced so the bearings failed, that's state of the art design work Acer!
Well if you where trying to design it to fail that is!

LOL at the fact that the speaker magnet was messing with the fan ... EPIC fail!

[catrios]

Re: Acer Aspire 5730Z bypass PWM fan requirement? 5930 too!

After finishing a Fullers Indiana Pale Ale something dawned on me:
I took a sledgehammer and flattened it's bottle cap:
...

Yeah baby, that's some real redneck modding for ya

Yes, yes, yes!
It worked for me too with Acer Aspire 5930!
Seems that ACER does it on purpose, and just particular genuine fans are the only "immune" ones (but they are expensive).
I've bought a visually identical fan from China (priced under 8$), described as „Original FORCECON DFS551305MC0T CPU Cooling FAN for Acer Aspire 5930 5930G fully test and free shipping ” but it didn't work (see picture - numbers are the only difference).
A bottle cap did its job in this case too, and the new fan is now humming quietly!

The only difference is that my Acer has a magnet not directly under the center of the fan, but about 2 cm away from the center – towards the radiator.
The cap simply stuck to the magnet, so it wouldn't need any sticking tape to immobilise it, but I still used it to stop the tremour.
It seems that the cap is not to shield the fan from the magnet, but to disperse the magnetic field, so it can be regular sticking-to-magnet-metal, not some aluminum, lead, or any shielding material.

Thanks!

[Per Hansson]

Re: Acer Aspire 5730Z bypass PWM fan requirement?

Welcome to Badcaps and thanks for posting about your success catrios!
I was wondering when someone else would run into the same issue, I thought it was quite funny

Mine also didn't have the magnet directly under the fan motor;
I think that is why the original fan failed actually as I wrote in my previous post...

[pawel_ch]

Re: Acer Aspire 5730Z bypass PWM fan requirement? 5930 too!

Yes, yes, yes!
It worked for me too with Acer Aspire 5930!
Seems that ACER does it on purpose, and just particular genuine fans are the only "immune" ones (but they are expensive).
I've bought a visually identical fan from China (priced under 8$), described as „Original FORCECON DFS551305MC0T CPU Cooling FAN for Acer Aspire 5930 5930G fully test and free shipping ” but it didn't work (see picture - numbers are the only difference).
A bottle cap did its job in this case too, and the new fan is now humming quietly!

The only difference is that my Acer has a magnet not directly under the center of the fan, but about 2 cm away from the center – towards the radiator.
The cap simply stuck to the magnet, so it wouldn't need any sticking tape to immobilise it, but I still used it to stop the tremour.
It seems that the cap is not to shield the fan from the magnet, but to disperse the magnetic field, so it can be regular sticking-to-magnet-metal, not some aluminum, lead, or any shielding material.

Thanks!

You have any photos of this solution?