Possible to Undervolt laptop FAN?

Hello Folks,

I have HP DV8000 Laptop With the following spec-

http://www.techshout.com/laptops/2006/07/hp-india-launches-pavilion-dv8216tx-notebook/

As monster as it is... I am very happy with it.. Esp Dual 7200 RPM HDDs in RAID 0.

The one and only thing I hate is... the fan!
Its almost always running (except the coldest winter nights) and Annoys me with great deal of noise.
This is the situation since day 1, So Its safe to assume HP designed it that way.

I've tried cleaning with compressed air, Running it without OS and etc... Same.
No Bios settings provided for fan.

Now as the warranty is over, Can I hard-mod the fan to a lower voltage?

I've done this 7v and 5v mods on MANY of desktop fans... Peace and quiet......Works flawlessly!

But with a laptop? Whats your say?

 

And yes, The temps-

Field Value
Sensor Properties
Sensor Type CPU, HDD, ACPI
GPU Sensor Type Maxim MAX6646 (NV-I2C 4Ch)

Temperatures
CPU 46 °C (120 °F)
CPU #1 / Core #1 44 °C (111 °F)
CPU #1 / Core #2 46 °C (115 °F)
GPU 40 °C (104 °F)
GPU Diode 42 °C (108 °F)
GPU Ambient 37 °C (99 °F)
Seagate ST980825AS 40 °C (106 °F)
Seagate ST980825AS 39 °C (102 °F)

Voltage Values
CPU Core 0.950 V



http://www.techshout.com/laptops/2006/07/hp-india-launches-pavilion-dv8216tx-notebook/

 

Try this first:
http://notebookequus.blogspot.com/2008/09/patching-dsdt-table.html

 

Thanks for digging it Up....

Sounds risky... But worth a try.

tell me........will it work always when the windows loads up? In any Application?

Will it work for any of the user accounts I use with windows?

 

yes to all of your questions.

It's not risky. If you have a problem, hold F8 and boot "last known good config".

 

Software is really the only thing you can do short of installing a resistor or microcontroller in a separate fan circuit. All laptop fans are 5V, so yes you can technically throw in a resistor to make it run at 4V but you are also decreasing the efficiency of the fan. The manufacturer surely tested that the fan needs to be spinning at such a speed to keep the laptop cool. Your modifications may inversely effect system life.

K-TRON

 

1. Have you checked out different bioses for your laptop and looked for anything about changes to the fan profile in their description?

2. Have you taken out the heatsink, cleaned it thoroughly, and used some top of the line thermal paste when you replaced it?

3. If you really want to go into modding it, I would install a tiny three way switch to connect the fan to either the stock power source and a straight 5v source depending on your mood. For the 5v source, put a tiny rheostat or variable resistor so that you can tweak it to your liking. The switch is there just in case you want to go back to the stock way whenever you want to. This way you gain the benefit of a fan completely under your control and the safety of the stock operation. I probably wouldn't do it to anything under warranty though, just in case.

 

I think you Guys are not versed with the well famous Dv8000 fan Issue.

HP purposefully designed them such that fan stays at High speed no matter what... Run a google scan, you'll soon know.

Actually.....

I am going to Totally......thoroughly Mod this lappy....

Pics and instructable coming up.......

Keek your eyes peeled!!!!!!!!!!

 

Make sure you pin mod the PLL.

 

I have made a supersimple (not super reliable) solution with my T2250 1,73 gHz.
There are one on/of switch on cooler, one red diode who lights, when notebook gives power to fan, and one green diode who lights when I have turned fan on!
So, when I am doing my office stuff, I turn off cooler (temperature stays at 50 celsius). When doing some harder stuff, turn cooler in. Plus, I configured speed fan to beep and give a pop up message when temperature reaches 60 celsius! There are risk, that I will leave fan in off positions, and go away, while some unknown software starts to stress cpu to 100%, but i think, notebook must turn off before it dies, because it do so, when I place it on a lap or other soft surface for a long. Ok, but that's just lyricism and not for your monster!

Fact is my new CQ61 fan kills me the same way, and there are almost nothing to do with dsdt table. I think to try undervolting http://forum.notebookreview.com/showthread.php?t=235824
but as I understand, it will not make much sence to my notebook idle temperature, and if it does, then my dsdt table will spoil it, coz fan spins at 37 celsius already!

Finaly I thing, i solve the problem with variable resistor + speed fan! If you do it first, give a note!

 

My good friend! I thought it is good idea to undervolt my compaq, since i did that on my old noname lappy by removing 5 screws to ge to fan wires. To get to Compaq Presario CQ61 fan i must remove back cover, batery, hdd, wifi, then keyboard from front.. thats how far i looked into service manual! Don wana go further. What a cheap crap hp made! Luckly, there are such lohs like me, to buy those!

 

Boss!! you're absolutely right!

I finally opened that laptop....
I fan frankly say it was one of the hardest! Toughest ! Sweatest and most time consuming surgery every done!!
i've torn over a dozen laptops myself,.... My DV8000 is in a league of its own!!!! Oh

I did set myself a new personal record tough!
NO SCREWS LEFT OVER... after such a Demanding job!

I've re-routed the wires and Packed back the machine.
Lets think what can be done with those wire now!!

http://s59.photobucket.com/albums/g317/bhvm/Flame teardown/

 

Congratulations bhvm! If U have wires now, its easy to find some potentiometer to put in chain!

Thats a nice violance of that stupid fan in your pistures

 

That is possibly the ugliest mod I've seen in a very long time. If I had to guess, you used either a pair of scissors or pliers to cut the plastics instead of a dremel or even tin snips, and I'm hoping those wires were properly soldered and insulated. Why not just snip one wire and stick in a resistor? It almost definitely would kill the fan sooner like K-tron said, but without all that teardown you did.

Now that you've done it, I'm sorry to say you probably have to take that entire piece of plastic off, clean up the raw edges, and drill holes for a grill you'll have to custom cut to cover the gaping maw you left there. I'd probably also throw a crossbar in there for support as well since it's such a big hold. Are those wires I see running through the heatsink as well?

 

The heatsink you added will keep the heat within the laptop. The heat pipe and fins were designed get hot and allow the air flowing through the fins to cool the laptop, the best thing you could have done (and i have done on a similar model) is to create a duct so that the hot air goes streight out of the vents at the back

At the moment the hot air leaving the original heatsink will heat up your heatsink and keep heat within the chassis. So not a good mod