I just got a PowerMac G5 (dual 2Ghz 2003 model). I notice that, of the two main fans on the rear of the computer, only one fan is blowing out air. Is it an air-exchange system or should they both be spinning the correct ways?
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Are the fans in my PowerMac G5 okay?
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Altemose
macrumors G3
Jessica Lares
macrumors G3
Make sure they're both even plugged in. I didn't even notice that one of mine weren't until my dad was helping me pull out the AirPort Extreme to put in the iMac G4.
And I was using it for a few years like that! Doing crazy things! 😱
And I was using it for a few years like that! Doing crazy things! 😱
Altemose
macrumors G3
What type of crazy things? I accidentally have run a G5 without the front fan assembly you remove to get to the memory.
Yes, I just verified that both are spinning. One is spinning the other direction then?? BTW, the Mac isn't having any temperature issues while this is going on. I have the computer exporting a high quality video and the CPUs are both pretty much maxed out, and the computer is at an average of 142 degrees. (a temp which is normal for my iMac G5 while it does minimal tasks like what I am doing right now by typing this).
EDIT: I found a post on a MacRumors thread, originally about some firmware update, (dang, the post is from Dec. 2003) and it says this:
"According to our independent analysis, the fan now spins at a higher rpm, but uses less electricity and kicks on less frequently. It also runs more quietly and with lower torque. Furthermore, from time to time it now automatically spins backwards for 30 secs at a time, thereby reducing the accumulation of dust on the fan blades, and preventing dead air hot zones within the cpu tower."
Granted, my G5's rear fans never seem to be alternating their directions at all--They remain the same. These are the ones that sit behind the processors. I would appreciate if you could tell me whether you feel air coming out of BOTH of the rear fans on your G5, or not.
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Jessica Lares
macrumors G3
I accidentally used mine without the plastic cover once. It roared.
Oh, you know, just used it normally. Ran Photoshop, used Flash, watched videos, and 3D programs. And in all that time, it didn't occur to me that one of the fans was disconnected.
Altemose
macrumors G3
Jessica Lares
macrumors G3
Very! But again, I didn't think much of it.
I also ran my 2006 MacBook Pro for two years without the left fan.
Altemose
macrumors G3
What fan was disconnected? You do understand that fans are there to be plugged in right? The same way you are supposed to park between the lines... 😛
bunnspecial
macrumors G3
Probably my worst G5 experience was when I left the fan disconnected on the graphics card after repasting the GPU.
The GPU was idling at about 110ºC, and the fans kept kicking on full blast(which really is loud!). Once I reconnected the fan on the card, everything was fine.
The GPU was idling at about 110ºC, and the fans kept kicking on full blast(which really is loud!). Once I reconnected the fan on the card, everything was fine.
Jessica Lares
macrumors G3
Of course. The one in my MBP broke because a piece of the plastic that holds the top case in place broke and fell into it (A Genius butchered my SuperDrive replacement). I just never bothered to replace it and the machine still works to this day.
On the G5, it's the one you pull out. I just never thought about it needing it to be plugged in. It wasn't stuck to anything to begin with.
Oh, and I don't drive, but I get what you're saying. LOL. 😛
Altemose
macrumors G3
So does your PowerMac G5 do that? Check and see--I hope this isn't some problem, especially a rare case. I'd like the thread to stay on the specific subject.
My PowerMac functions similarly. I've always assumed that it is not a defect, as nothing bad has come from it.
Altemose
macrumors G3
I have noticed that one fan is stronger. The bottom is usually weaker on mine.
Interesting... I wonder if the fan behaviors were pretty different depending on the processor speed. Anyway, my brother told me that his Mac Pro has fans on the back that both blow out air and take in air. I have decided that what is going on with my G5 most likely is NOT an issue considering:
1. No problems have occurred as a result of this backwards-spinning fan
2. The Mac Pro is pretty similar to the G5. I am sure it adopted this intake/outtake architecture from the G5, with its fans
3. That old post claimed that the G5 had its fans switch directions to eliminate any dust or air pockets in the system. Even though mine stays put in the opposite direction and never seems to be alternating, I stand firm by that reason.
4. I have NEVER heard of this 'issue'. It seems to not exist. I know most do not stick their hand behind their G5 to feel the air, but it seems like something that others would have noticed as well. I cannot be the only one...
G51989
macrumors 68030
Make sure they are both still plugged in.
Ive owned several G5s, some of them brand new, depending on the program, one CPU will heat up more than the other one, dual fans for each CPU, ive had one fan go, or another, ive had both fans blow **** off the back of my desk during intense CAD or gaming stuff.
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I gotta say this is not correct, at least on the 3 G5s I own ( two of the from brand new ), the part number, and fans are the same.
Altemose
macrumors G3
Guess I have a defective fan assembly and will need to replace the part then... Guess it is better to know than burn something out.
G51989
macrumors 68030
Yeah, I don't use my G5 anymore, but the part numbers on both fans are the same man, time to order replacement.
Both of mine are spinning, but one doesn't blow out air... The top one is spinning backwards.
G51989
macrumors 68030
Time to replace said fan, its got a short in it that makes it spin backwards.
Even if there aren't any heating issues? CPU A is running at 114F with this Safari page open, and CPU B is running at 100F. Also, iStat menus shows this:
"Intake". Which fans are the sensors referring to? BTW, if there are REAL intake fans and the one that I have taking in air is NOT supposed to be doing that, then I have found replacements on eBay for cheap. However, is there a difference between the exhaust fans on my 2003 model and the late 2005 model? I have found one for $2.07 and free shipping and I really want to get that, but it says 'Late 2005'.
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G51989
macrumors 68030
Both fans are variable, if one isnt behaving like the other, its time to replace both.
If you can find stock apple fans, great. Buy them