Laptop Cooling Stations: are they worth it?

[weberdarren97]

Hello all,
I am doing a basic experiment with my laptop... It's an old Dell Latitude D620 series and it's physically the same as it was when it was bought in 2008 other than the fact that the two 1GB DIMMs have been replaced with two 2GB DIMMs. It's currently running Windows 10 32-bit as it has a x86 CPU.

So here's the testing scenario. I did what I thought the average person with little to no knowledge of computers would do... I went to the local resale store and bought the cheapest laptop cooling station that they had. I ended up with a model from iHome, costing about $4.

Three tests were performed. In the first test, the laptop was just sitting on the counter as if it was sitting on my lap (I used the counter to remove body heat as a variable). In the second test, the laptop was sitting on the cooling station but the cooling station was not powered on. In the third test, the laptop was sitting on the cooling station which was powered on. Between each test, I took the laptop into my storage room kept at 65 degrees Fahrenheit and left it there for one hour with the screen open to let heat drift out through the keyboard. This was to make sure that there was nominal heat left in the system from the previous test, as to not invalidate test results. To raise temps, I used AIDA64 Extreme's built in System Stability Test feature and stressed everything for fifteen minutes except for the local disk. The reason I didn't test the hard drive is because I didn't want it's age to hinder results by failing to record statistics due to being overloaded... I also didn't want it to fail, which would invalidate all results.

Each test was performed three times, the graphs are the average results.

Here are the results. I will explain below what I think is going on here.

I noticed several things that stood out to me.

First is that the cooling station itself seemed to lower CPU temperatures without even being powered on. I thought that this was likely because the laptop that I used for this test has its intakes on the bottom, making any extra room below the laptop beneficial to internal cooling systems. Also, I noticed that there was less of a difference in CPU temps between having the cooling station on and off as there was between having the cooling station off and not having it at all. Taking a look at internal fan speeds, I can see why this is. The fan ran much faster when the laptop was elevated onto the cooling station which was not powered on. I think that this is because the fan didn't have as much resistance below the laptop as there was more room between it and the counter, allowing greater airs speeds, which would allow the fan to spin faster while receiving the same voltage and/or PWM signals. Also, the fan span slower when the cooling station was powered on, and this was expected. The extra air pressure from below would have allowed the fan to reach the same air speed at a lower RPM (like using push-pull on a radiator).

Moving onto DIMM temperatures, I noticed that they ran the coolest when on the counter, hottest when on the cooling station while it was powered off, and ran within one degree of the control when the cooling station was turned on. To me, it seems like allowing the fan to run faster by reducing resistance at the bottom intake has changed airflow patterns within the machine.

I thought about using a dye test to see airflow, but realized that opening up the machine would change internal pressures which would invalidate results, I also realized that the machine has only one exhaust, which means that looking for a change in airflow patterns below the motherboard is impossible because the motherboard is mounted to the bottom half of the casing.

It also seems like introducing extra air pressure from the cooling station, which allows the fan to run 30RPM slower, slows down airflow under the motherboard enough to raise DIMM temperatures by one degree on average.

The reason I think that airflow under the motherboard has changed is because the CPU fan is the only fan in the system, and it's near the rear-left corner. There is a door with airflow slits cut in it which appears to be centered on the bottom, right below the DIMMs. I think that pushing air in that door instead of letting the fan suck it in may have made the air hit the sides of the DIMMs instead of being pulled across them, since they lay flat, parallel with the motherboard.

All in all, it looks like getting a laptop cooling station does more of moving heat around within the laptop rather than getting it out of the laptop. After this testing, I cannot say that I recommend these cheap cooling stations for the Dell Latitude D620 series because it raises temperatures in certain areas of the machine while lowering it in other areas.

Conclusion: Don't expect a good cooling solution for $4.

 

[penguintech]

Interesting testing, but who would expect a $4 solution for laptop cooling? No one I really know would think they would get any kind of cooling power from a $4 knockoff.

 

[bboiprfsr]

The CPU core temps decreased by 8C along with the CPU package decreasing 6C with the laptop cooling station. That's pretty significant in my book. Also 1 degree Celsius is marginal/experimental error. Altogether I'd say it's worth it. Not only will your lap not feel the heat if you're sitting on a couch, but it's better ventilated with than without it. Sorry bud, but I see longevity in this investment. Thanks for putting forth your experimental report. Well done. I just don't agree with your conclusive remark

And by the way, in desktops people pay extra premium $$'s just to get lower temps (i.e. spending $90 on a double tower heatsink, double fans, 12 copper heatpipes vs a $45 single tower, single fan, 6 copper heatpipes for a 10 C difference at overclock load temperatures). I don't understand your logical reasoning. I mean you can feel the difference in outside temperature between 20C inside temperature to 30C outside temperature, right? The impact is significant... PERIOD.

 

[bboiprfsr]

Let me rant some more. The way a laptop is built (compact) is really dependent on its management of CPU temperature. If the laptop overheats, your other internal components will FEEL the heat and get hot as well - which in turn affects damaged transistors, faulty motherboards, and so on. So instead of having a HEATED argument, let's be COOL with it xD

 

[1shado1]

Interesting testing, but who would expect a $4 solution for laptop cooling? No one I really know would think they would get any kind of cooling power from a $4 knockoff.

He said he purchased it from his local resale store. I'm guessing it was probably used, so may very well have been sold for 30 or 40 bucks when new. That we just don't know.

 

[penguintech]

I own a store that sells refurbished equipment but something like our cooling fans are new. Honestly we pay about $1.45 for each new fan and resell for $7.95. I wouldn't expect any kind of performance out of it though. If I bought one for personal use I would at least spend $20 or more. He should re-do this test with one that is known to actually work as described... I am sure the results would be much different.

 

[weberdarren97]

I do plan on doing another set of tests with a higher quality product. This test was aimed at the user who has little to no knowledge of computers, has bought a very cheap laptop and is going shopping for a cheap cooling solution.

 

[penguintech]

Understandable.... I wasn't trying to come off as rude, I would enjoy seeing the same type of testing with one thats worth the money.

 

[weberdarren97]

Well right now I'm working on optimizing the code in my website for multiple browsers... It'll be probably a little over a week before I can start more testing.

 

[kdblueey]

Interesting and very thorough testing you've done. WOW! Do you think if you paid more than $4 for the cooling system/fan, that you would have gotten better results?

Here is my experience with overheated laptops and external cooling fans. I purchased a Lenovo Ideapad 100-151BD series in October 2015. I also purchased an external heating fan, made by BELKIN and paid $29 for it. But I started having problems with my laptop overheating, mainly on the left side, underneath. Lenovo replaced the motherboard. When I got it home, I noticed (after a month or so), that it was doing the same thing, but this time, it was overheating on the top right side of the laptop. So then Lenovo replaced the graphics video card. I haven't had any problems with overheating since then and this was in June.

I have also read and heard that most external cooling fans don't last long. This I have found to be absolutely true. My BELKIN fan is on the fritz (it lasted around six months), so I will not hesitate to go back to Walmart and purchase another one. Being as laptops are compact, an external fan is essential in maintaining the correct core temperature, and keeping your laptop safe from overheating

Thanks for listening

 

[John Chapman]

I've had a number of laptops over the years. Some developed overheating problems, Others were fine. In an extreme case one laptop, which remained on while the lid was closed, actually partially melted the keyboard.

Invariably the problem is caused by dust which collects. Sometimes you can remove this using a vacuum cleaner hose but some laptops - especially those made by HP have a dust trap between fan and the fins of the heat exchanger. If you have a cat this can be much worse since cat hair gets trapped here and normally can't easily be removed without completely dismantling the laptop. That's not a solution I would recommend to an average user.

Got a cat? There is a simple fix. You'll need a sharp craft knife and some stiff mono-filament fishing line. It needs to be stiff but narrow enough to fit between the cooling vent fins. Cut the line at an angle to make a sharp point. You'll need about 15 cm. Make a second cut, also at an angle but not all the way through and just behind the point. Twist the blade to make this bit stick out forming a hook. Use your 'hook' to go fishing for those cat hairs through the outlet vent. It will take time and patience but it will clear the vent.