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xe0 · Mar 29, 2004, 02:31 AM

I just had the weirdest thing happen..

Ok. I was working on a magazine cover. I had several versions Im working on, which were all open. All about 40meg in size, each.
About 5 mins ago, I decided to reboot as Ive only got 512 ram in G5 atm.
I could feel the system starting to chug a bit, just due to the fact it had been on for a few days, without a reboot and I had been working all day with large files.

A simple and regular procedure.

OK. so I reboot and decide to go outside & have a smoke, so I can think about a few things I have to do with the covers.

When I came back to my studio, I could hear what can only be described as a loud whirlwind..
I paused at the door, thinking It was just my XP box (its loud as hell) but then I quickly realized that the sound was way to loud to be coming from the PC and... it wasn't on.

I hurried over to the G5 only to realize the fans were on full speed... but like ultra full speed. Like.. Ive never heard the G5 crank up that much. It was incredible.. I thought it was going to take flight they were going that hard.

I tried moving the mouse to see what was happening on screen, but the G5 hadn't even properly reset? the monitor was off and moving the mouse did nothing.

I panicked and opened the G5 case to see what was going on, leaving the clear plastic. By what I could tell every single fan was going at its maximum speed. Even though the sound it was making sounded... well... not right. It was way too loud. Then the fans started getting even faster.. I could hear the pitch getting worse...

So I held the power button in, turned it off and waited a few seconds- then booted back up. Then, everything was ok? The fans are back to normal, and the system is as it should be?

WTF happened?! I really can't stress how fast the fans were spinning. There was defiantly something wrong. I dont want to think of what would have happend if I didnt return..

has anyone else had this before? Im running a stock Dual 1.8Ghz G5 | 10.3.3 |

cheers in advance.

striker100 · Mar 29, 2004, 05:12 AM

A similar thing happened to me. I was working on my G5 when the phone rang so I put the G5 to sleep, but instead of going to sleep it comes on again and the fans start whirring up like a large wind tunnel.
I swear I thought the thing was gonna explode! Shocked I quickly held the power button down to turn it off.
I waited about 5 minutes and turned it back on and all was well, it was the one and only time this happened.

Mac Zealot · Mar 29, 2004, 05:13 AM

Odd, but not too odd.

When my g4 was new every now and then if I reset it, it'd hang on the reset and that sort of thing DID happen.

That's just odd. Might be a motherboard problem, but I doubt the fans would have "blown out", they do have a maximum before they can't go any faster... you just experienced 9 delta fans running full blast :grin:

I can hardly wait to see the comments following this.

southtdi · Mar 29, 2004, 11:40 AM

Not saying that is normal but I have had my fans at full blast during the hardware test (I think it is normal for it to do it for the test). Actually atarted getting me nervous at how loud and how much air it was blowing and it kept getting faster. All I can say is when they get to full power they can move an incredible amount of air.

Turias · Mar 29, 2004, 11:49 AM

It's a safety precaution that kicks in when the computer freezes to make sure that nothing inside overheats. Don't worry over it more than you would worry over any other computer freeze.

Immortal K-Mart Employee · Mar 29, 2004, 11:55 AM

Relax it is NORMAL. The fans are software controlled. When your g5 crashes the machine goes into panic/safe mode and just cranks the fans into full to make sure it doesn't melt.

ThisGuy · Mar 29, 2004, 12:14 PM

i was setting 3 of them up when they were first released when they were booted into target mode they did the same thing. they guy who i was working for came in and said, "i sure as hell hope that thing quiets down when i have to work on it." i have no idea if any firmware updates or anything corrected it. what Immortal K-Mart Employee said makes sense to me.

djohnson · Mar 29, 2004, 01:56 PM

Automatic a/c... well maybe fans... Pretty cool if you think about it.

Immortal K-Mart Employee · Mar 29, 2004, 03:31 PM

Originally posted by ThisGuy:
i was setting 3 of them up when they were first released when they were booted into target mode they did the same thing. they guy who i was working for came in and said, "i sure as hell hope that thing quiets down when i have to work on it." i have no idea if any firmware updates or anything corrected it. what Immortal K-Mart Employee said makes sense to me.

In target mode they do not have software to control them so they go full blast. The newer ROM updates make them less nuts though I hear.

tooki · Mar 30, 2004, 01:20 AM

Basically, unless the software (that is, Mac OS X) continuously tells the fan controller to keep them running slowly, then the fans will automatically spin all the way up to ensure the computer doesn't burn up. Think of the software as a moderating force; when it's absent (because you've booted into another OS, or the OS has crashed), the fans don't have anything telling them to spin down, so they go full blast.

tooki

xe0 · Mar 30, 2004, 02:18 AM

thanks for the answers guys. It doesn't worry me to much now considering the reason is apparently a built in security measure.

Man, I was expecting the G5 to seriously propel it self through the wall. Kinda like the Old G5 ad, where the G5 blows the guy away.. except in this instance it would be the G5 blowing itself away

Mac Zealot · Mar 30, 2004, 03:09 AM

The built in fan controller is great, but personally I think the machine should have a built in fall back.

tooki · Mar 30, 2004, 05:55 AM

Fall back to what? It seems to me that the current solution (default to I'm-gonna-make-sure-I-don't-self-destruct-mode) is a pretty darned smart one. I'd rather it default to overcooling in the event of a crash than to have it overheat.

tooki

danbrew · Mar 30, 2004, 09:30 AM

Which way do the fans rotate down there in Oz? Do they go opposite like the drains? Maybe that's why it got so hot?

xe0 · Mar 30, 2004, 03:25 PM

Originally posted by danbrew:
Which way do the fans rotate down there in Oz? Do they go opposite like the drains? Maybe that's why it got so hot?

LOL

yeah Im with tooki on that one. I too would much rarther have the system go into an over precautionary mode and cool itself (and the house) as opposed to having a potential core meltdown.