X41 pasive cooling options ?

[Akira_Hotate]

Hello. Recently I have acquired an IBM x41 laptop. I just love it, how light and portable it is.
I have upgraded it with 2gb ddr 800 ram, a 16 GB 1066x CF drive (debian boots to gnome3 in 20 seconds).
I'm planing to buy a new replacement battery. And since I am trying to make a somewhat netbook replacement, I was wondering, would it be possible to hack a passive Thermoelectric Cooler (Peltier Cooler) instead of that annoying fan.

I know that the CPU Tjunction is 100 C
It usually runs around 45-55 C
On max stress test it reaches 70 C

I was wondering If I would remove the FAN, solder a resistor instead (to bypass the fan error), and install something like this on the heat sink:
http://www.ebay.com/itm/DC-5V-19-4W-The ... 27f5264dc8

Any ideas, suggestions, opinions would be greatly appreciated.

[RealBlackStuff]

No idea if that is doable, but I would strongly suspect a large drain on your battery with that.
After all, it would be permanently ON.

[rkawakami]

Peltier junctions can indeed cool surfaces when a current is applied through them. However, the downside of this cooling is that the opposite side of the panel / plate is heating. Yes you are essentially subtracting out the heat from the heatsink (and by thermal conductance, the CPU) but replacing it with heat from the Peltier effect. Since there's no active cooling on that surface, other than air conduction, you'll be increasing the interior temperature of the laptop, and as RBS indicates, draining your battery faster. If the 19.4W spec is accurate, that would represent about 1/3 of the power available from a new battery, assuming you have a 60Wh unit. So, if you normally get 3 hours of life from the battery, you'll get around 2 hours using the thermoelectric cooler.

[ajkula66]

FWIW...

I've owned a couple of Panasonic CF-R4 Let's Note machines that belong to the same era/platform as X41, but do not utilize active cooling. ULV CPU or not, these things ran hot under any remotely serious load.

Generally speaking, I'd pass on the concept of downgrading the cooling on ThinkPads, as imperfect as it may be.

My $0.02 only...

[Akira_Hotate]

Hmmm. Now that you put it this way. I guess the thermoelectric cooling is not such a good idea.
Wheal my x41 fan makes kinda funny noises. When it is spinning and you tilt the laptop, you can hear the fan blades touching something and making a noise. I guess I will have to replace the fan at some point. I had the idea of getting rid of the fan entirely, like on the new (crappy) lenovo flex models.

I guess I need to think about other ways to cool it, or just fix/replace the fan.

Thank you for your information.
If you have more ideas on this topic, please share them.

[siya-u]

First, try to undervolt CPU core voltage with a software like Notebook Hardware Control or RMClock. You can also limit the highest CPU frequency with these software.

Second, if you don't want to install a new heatsink-fan unit, remove the old one from system board, lubricate the fan bearings and apply some thermal grease with a famous brand (eg. Arctic Cooling MX4).

Third, use Thinkpad Fan Control software to control when the fan kicks in and out.

I've managed to reduce my X41's load temps by approx. 10 degC. Idle temps are even lower. The fan is passive when the system is idle, and active when CPU reaches 70 degC. Most of the time, I have a dead-silent machine.

[axur-delmeria]

I had the idea of getting rid of the fan entirely, like on the new (crappy) lenovo flex models.

I just looked at the HMM of the Flex 2 (14 and 15 inch) and it looks like there's a fan.

[Qing Dao]

I know I'm late to the party, but for any Peltier / TEC, you need a much larger heatsink, since you will need to get rid of the energy used by the chip, plus the even greater amount of energy used by the TEC. These things are good for cooling things down with no active source of heat, but once you have any sort of heat source, things get quickly out of hand. They fell out of favor for cooling desktop CPU's and GPU's around ten years ago because of the ever increasing heat output of chips. They also are only used for cooling things to below sub-ambient temperatures. If you don't need to go below ambient, just getting a bigger heatsink or going with water cooling without a TEC is far more practical and won't triple or quadruple power consumption.

If one really wanted to passively cool an X41, or any computer for that matter, they would need to minimize heat output and increase the ability to dissipate heat. The hardest part is increasing the ability to dissipate heat. The stock heatsink, stuck inside the case with no airflow, is not going to cut it. There are two other large heatsinks that can be taken advantage of though, the large steel plate that is the back of the keyboard, and (I'm guessing based on other Thinkpads) the magnesium case. Copper shims, thermal pads, and heatpipes would be required to get the heat to those sources. Shims and thermal pads should be easy, heatpipes not so much. Minimizing heat output is done in two ways, undervolting and underclocking. Undervolting is critical as the power consumption reduces by the difference of the squared voltages. For example, if you halve the voltage, you have one-fourth the power consumption. The best way to undervolt for a project like this is to do it manually with variable resistors between a power source and the voltage-sens line on the voltage regulator chips. You can do this for the processor, chipset, and RAM for a triple whammy. Underclocking is beneficial too. If you halve the frequency, you halve the power consumption. But perhaps just as importantly, lowering the frequency allows you to lower the voltage further. How far you need to underclock and undervolt is just a function of how well the heatsinks work and what temperatures you are willing to live with, as regardless, it will run hot.

[ZAGNUT]

RMClock as mentioned in previous posts. somewhere there is a list of "reliable" voltages for the X41 and just using those without any further experimentation my machine is silent 95% of the time.

the HDD also makes a lot of noise and that got shut up by going with the SATA SSD mod.

working on a way to silence the voices in my head now...