How Hot is Too Hot? (Mac G5 ISO BOX)

[jaysunice]

I'm just about to finish up my custom-made-self-built ISO BOX for my Dual 2 GHz G5 and Glyph Firewire External Hard Drive. It's made with 1/2" MDF and lined with 1" Auralex Foam, as well as some standard packing insulation. I also drilled a 2" Diameter Hole in the Back (to allow for cords), in addition to medium sized vent (2" x 8" approx.) along the Back of the casing.

While my G5 never generated too much heat out of the box, it did make too much noise for my liking, thus the building of the ISO BOX. I'm going to throw a thermometer in there, but I don't know exactly how hot is TOO HOT? Any insight on the issue is more than appreciated.

[jaysunice]

NOBODY????

[Jazzy Alz]

I've got no idea dude!

[tINY]

It depends on the thermal design of that system. I'd be suprised if it doesn't work pretty well at an ambient temperature of 100° F - with normal airflow.

But, you've gone and changed the airflow, havent' you?

I imagine the processor has some way to monitor it's own temperature and will take steps to stay alive - read your manual.

Remember that you can add airflow by creating muffled plenums for circulation.

http://www.acousticsciences.com/nois...les_index.html

(for some ideas ^ )




-tINY

[jaysunice]

I'm a little confused as to why I would change the airflow? Correct me if I'm wrong, but I thought Macintosh had gone to great lengths to create an extremely efficient front-to-back airflow? I believe the even suggest to keep computer doors shut while running?

[dkatz42]

Originally Posted by jaysunice

I'm a little confused as to why I would change the airflow? Correct me if I'm wrong, but I thought Macintosh had gone to great lengths to create an extremely efficient front-to-back airflow? I believe the even suggest to keep computer doors shut while running?

The primary issue is that you're likely to be pulling in much warmer air than you would be if it were free-standing, so there will be less cooling going on.

Additionally, putting the computer in a box may reduce the airflow through it somewhat, depending on the construction and how close the computer's vents are to the walls of the box--it may raise the static air pressure at the exhaust end, which will reduce the volume of air moving through the machine.

The G5 will compensate for the temperature by running its fans faster and faster, potentially with your whole system ending up louder than it would have been with the G5 freestanding (a G5 with fans at full speed sounds a lot like an airliner.) I suspect that the G5 will shut itself down rather than allow itself to burn up if the temps get too high.

A single vent is going to be pretty inefficient in terms of cooling the box, though the cord hole will help. The air just isn't going to flow very well. Two smaller vents (one toward the bottom and one toward the top) should help--the natural convection will provide air flow through the box.

Ultimately you'll probably just have to try it, and tinker, and see how it goes.

[jt916]

I built an ISO box similiar to yours for my G5. For mine, all the air ventings were done at the back of the unit. Top part, of the back, I am using Raxxess quiet fan (2's) facing inward, the bottom part, I also use another set of Raxxess quiet fans facing outward. The whole ISO unit is tucked away from my work station with its back facing the wall with acoustic foam padding.

I manage to keep the entire unit pretty cool running all day.

hope that help.

[jaysunice]

I just want to say thanks for all the input. Gearslutz is truly wonderful.

[dkatz42]

Originally Posted by jt916

Top part, of the back, I am using Raxxess quiet fan (2's) facing inward, the bottom part, I also use another set of Raxxess quiet fans facing outward.

You might be better off if you turn the fans around; you're fighting the tendency for the warm air to rise. On the other hand, it works, so no matter.

[nathanvacha]

Originally Posted by dkatz42

You might be better off if you turn the fans around; you're fighting the tendency for the warm air to rise. On the other hand, it works, so no matter.

I was going to suggest the exact same thing. Also, If the G5 pulls air through front to back, you may want to baffle your box so that the fans pushing air in at the bottom are below a shelf that your computer would sit on. The "shelf" should be flush (or even sealed) against the back and open at the front. This way, you would pull cool air in near the floor which would get sucked in at the front of your computer and blown out the back where it would rise to the top of the case and be sucked out at the top of the back.