Bluefront's Laptop Cooler.

[Bluefront]

This is my first attempt at this sort of device, and it really works. This is a Thinkpad 570, pII-385, 320mb ram, 50 gb Fujitsu HD. It runs hot sitting on your lap....after a few minutes you couldn't stand it. The output temp of the CPU fan opening is over 50C, with the CPU fan maxed out and noisy.

This device is made of an oak kitchen drawer insert (for cuttlery). I cut it slightly so the pcmcia cards can be inserted....and I cut holes in the rear to match the output slot of a USB powered CompUSA plastic laptop cooler. The cooler wedges in the oak box using glued-together pieces of safety mat foam. I spaced the cooler up high enough so the rear ports on the laptop are unobstructed.

The laptop just sits on the cooler, partially wedged in by the foam...removes instantly. Amazing temp drop....at max CPU usage I now measure 36C, with the CPU fan barely turning. The little 40mm fans run on 5V, and are somewhat noisy. With a slight voltage reduction, they should be quieter than the original setup. With these fans running, the CPU fan slows way down, and is hardly audible.

This setup is much more stable than just sitting the laptop on the bare cooler.....no tendency to slip off. My lap is now very cool.



Other photos

edit....I lowered the voltage to the cooler fans down to 3.25V. They still start ok, blow less air, but the temps are the same as at 5V. But now the whole thing is virtually silent on my lap.....and completely so at arm's length. Great......

[Bluefront]

I added a little bling to the setup....a set of lcd temp displays. The sensors just push up on the bottom of the laptop, on the two hot spots....under the cpu and under the HD. I was pretty lucky with this setup in that the two left-most fans matchup with the hotspots.

What makes this setup very quiet is that the cooler/fan assy is embedded in this oak/foam enclosure. It is very quiet and keeps the temps way down.

[cAPSLOCK]

I friend of mine has a laptop of a similar age that also has temp problems, he finds that it helps a lot to just put it on a couple of cd cases, so that some air can flow under.

I'm wondering if it's normal for laptops of that era, or is it a cooncidence, or is it dust buildup? Have you had a look inside?

It really surprises me that some laptop cooler with small fans can be silent... I've always scoffed at them.

[Bluefront]

This laptop has had virtually no usage, and it's clean as a pin. I've had little experience with these things, so I don't know much about these matters concerning laptop heat.

But using it as intended is rather uncomfortable. At 3.25V the cooler is quiet.....but not so at 5V. It's too old to have a CPU sensor that Speedfan can read, but I can measure the temp at the fan output hole, and at the bottom of the case. There's sort-of a metal plate that acts as a heatsink.

It's quiet and cool now.....

[BillyBuerger]

Wow, that is really neat. I've thought about something like that before. I use an old piano bench to set my laptop on at home. I thought about putting a hole in it for a fan. My Gateway 3018GZ (Celeron M 1.3Ghz) has an annoying fan even at 5V. Although your idea would work if it was on my lap as well.

But I still don't know if it would help as the bottom of my laptop doesn't get that warm unless I'm doing some real intensive work. Even at idle in a cool room, the CPU fan turns on at it's low 5V setting. I don't know if an external fan could really keep that from happening.

My current idea is to see if I can make the heatsink exhaust opening a little bigger and maybe even solder in some extra copper fins. I think there's enough room to do it. I'll post if I ever get up the guts to try it. I would probably still need to put a resistor or something on the fan to reduce the speed some more. The extra cooling area will hopefully make up the difference in the reduced air flow.