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Posted: Fri Oct 22, 2004 12:33 am
by hostile
Trip wrote:So air could still go in around the intake fan?
No, not really.

Now that the temperature has dropped decently here over the last couple of days, my temps are much better.

As I write this, I'm at 35C CPU / 23C System.

Pretty sweet.


Posted: Fri Oct 22, 2004 6:03 am
by Trip
Oh, well then like Rusty said, mostly only the CFM of the lesser fan is passing through the case.

I'm gonna try this in the next system I build, though I'll be using Nexus 12cm fans for sure.

Use a cheap infra-red thermometer. And incense smoke!

Posted: Mon Dec 27, 2004 4:50 pm
by gregzeng
hostile wrote:
markjia wrote:Why not try negative case pressure? If you are concerned about dust, maybe you can filter the other opennings in the case.
Currently it is running on a negative pressure setup. Just the stock fan is in place, and all the front is sealed up with HVAC tape, as you can see in the pics above.

So far, this setup seems to give the overall best cooling, which I find to be very counter-intuitive.
On AIR-PRESSURE differentials, I think the discussion should be instead on AIR-FLOW directions.

Tried to get the correct quotes from UR post, but couldn't.

On measuring the parts inside UR case (OR around the outsides of this hot notebook computer) ... use the cheap infra-red thermometer from the local drug store, Kmart, etc ... that's used to measure the temperature inside a baby's ear.

That way you can literally SEE (+ or - 0.1 degree differences) the sides/ top/ bottom temperature differences of almost anything in your computers.

For REMOTE temp monitoring, you can also look at two-temperature digital room/ car/ fish-tank thermometer.

But how to cheaply & quickly measure air-flow (the smoke of incense sticks?) & sound level output ... I'm still thinking!

Posted: Tue Dec 28, 2004 10:22 pm
by LH
Try using an undervolted or slow 80mm intake fan (like a Nexus 80mm). Since an 80mm fan won’t cover up the entire 120mm opening, I’m thinking some incoming air will be able to bypass the intake fan. Thus, the lower-of-two-fans-in-series airflow principle might not hold because not all the incoming air has to go through the intake fan.

Since the slow intake fan will only provide a bit of airflow, I’m thinking the exhaust fan would try to obtain the rest of its airflow “quota” through the the uncovered intake openings. There might be some internal air turbulence issues from interaction with the airflow from the intake fan, but hopefully it will provide better hard-drive cooling with minimal increases in case and CPU temperatures.

I’d love to personally test out this setup and report the results, but I unfortunately, I can’t... But, I’m sure others have tried this setup before.