Thread
IT BURNS!
hi all-
as you may have become aware, i recently got a new(ish) iMac g3. however, it gets HOT! i did some research and found out it's cooled via convection, which seems unhealthy. is there any place i can install an internal fan ?
-CT
as you may have become aware, i recently got a new(ish) iMac g3. however, it gets HOT! i did some research and found out it's cooled via convection, which seems unhealthy. is there any place i can install an internal fan ?
-CT
Dunno about iMacs & Fans, but convection should work. Have you blown all the dust out of every nook & cranny in the beast yet?
p.s. I fixed your typo.
)
I opened up a bondi blue iMac about a year ago and found that there was a fan hidden deep inside of it, which surprised me.
Did it say "boo!"
yes some did have fans buried deep in them, but aside from the first couple generations, I couldn't tell you which ones
and they still ran quite warm, at the time I figured where it was could not be effectively cooled by convection so they had to move some air one way or another, they choose a slow moving fan
and they still ran quite warm, at the time I figured where it was could not be effectively cooled by convection so they had to move some air one way or another, they choose a slow moving fan
Nay.
I've got half a dozen G3 iMacs still in regular use and they all get quite warm to the touch -- never had any problems other than 1 dead HDD, so my guess is that the convection cooling is quite adequate.
I have a 700mhz slot load and it gets extremely hot. The problem with adding a fan is where do you draw power from? Are there any extra pigtails coming off the power supply? I wouldn't think so. The best you could probably do is find a fan big enough to place over the carry handle where the hot air exits and set it up to draw out the air from the outside rather than push it out from the inside using an external power source.
Oh, BTW, with all that heat being expelled directly onto the handle, I wouldn't try carrying it without having at least one hand securely placed underneath at all times. Heat + plastic parts = brittle. The handle on mine creaks and groans under the full weight so I just lift from the bottom with both hands. Better that than having it hit the ground and smashing the CRT.
Oh, BTW, with all that heat being expelled directly onto the handle, I wouldn't try carrying it without having at least one hand securely placed underneath at all times. Heat + plastic parts = brittle. The handle on mine creaks and groans under the full weight so I just lift from the bottom with both hands. Better that than having it hit the ground and smashing the CRT.
I had an old pc case fan in my 350MHz iMac G3. I pulled off the connector and stuck the two wires into the positive and negative of the hard drive power plug and just jammed the thing into the hard drive's power outlet. It powered and worked well, but I don't think it did anything.
they make Y connectors so you could plug it into your hard disk
ALL Tray loading iMacs (the original 233 Mhz Bondi iMacs, and the first Rev. C/D (266/333 Mhz) fruit flavoured models) had fans in them, it wasn't until the slot load iMac/iMac DV/iMac DV SE came out in late 1999 that they went fanless.
And yes, even the tray load iMacs with fans do run very hot. For the past two summers I've actually run my iMac 333 with an external display, that way the internal display remains off and the system runs much, much cooler, so cool in fact that the top of the machine feels just as cool as it would if the machine had been off, even after running all day. I started doing it in Summer 2008/2009 when I became concerned about how hot that machine gets during Summer. This Summer its been running with the external display since November, and it'll probably stay that way until the end of this month, or whenever the climate cools down a bit.
Every fan I have ever bought has come with one. And screws too.
The real problem, IMHO, is working out where to put the fan. The existing cooling holes around the handle would be the logical place - if it wasn't for the handle in the way.
I just hauled one out to have a look. It looks as though there is room to put a large, flat fan behind the handle recess, and mount it in a shroud to direct all the air out the holes. Being large you could probably undervolt it to run quiet.
Beware CRT yaddah yaddah
I just hauled one out to have a look. It looks as though there is room to put a large, flat fan behind the handle recess, and mount it in a shroud to direct all the air out the holes. Being large you could probably undervolt it to run quiet.
Beware CRT yaddah yaddah
Unless it is super high CFM then generally the smaller ones are the loudest. You do not need that much flow really, so a slow large 140mm or something would be perfect. Barely audible but still decent flow. You are more likely to be annoyed by most of the HDDs than a good fan running at 12v.
aye, in my pc the power supply has a slow moving 130mm fan, it moves about the same amount of air as 2 60mm fans in the previous power supply, but you cant even here it over the hard disk (or cpu fan or gpu fan heh)
Mine seemed awful hot too, so I added a fan at the top of the case blowing air out the handle holes. The fan doesn't fit flush, so the sides of the fan are sealed to the case with clear tape to make an air duct. Keeps it much cooler with the forced airflow, and the fan has blue LEDs. 
Picture here, tho it doesn't show the fan's mounting details:
http://homepage.mac.com/henryspragens/PhotoAlbum17.html
Picture here, tho it doesn't show the fan's mounting details:
http://homepage.mac.com/henryspragens/PhotoAlbum17.html
Looking at your pic, it seems clear that the vent holes are not at the highest part of the case, when the Mac is mounted at that angle. Would propping it forward such that the vent is at the top help?
Another thing - after blowing one power supply in an iMac 450, I made sure there was enough space under the Mac for cool air to get in as well. I used the front fold out foot, and a couple of small blocks of wood at the rear.
THere's always the olde MacChimney approach, too.
Another thing - after blowing one power supply in an iMac 450, I made sure there was enough space under the Mac for cool air to get in as well. I used the front fold out foot, and a couple of small blocks of wood at the rear.
THere's always the olde MacChimney approach, too.
I'd make one up in clear plexi, rig it like a mast with a yardarm and sail, and then hang the Pirate Flag on it! :rambo:
True, but the highest part of the case contains only the top of the CRT. As I found when designing the Fanny Mac, all you have to do is actively suck the hot stagnant air out of the case, and the works will run much cooler. Obviously from a cooling perspective it would help if the air outlet was at the very top. An iChimney would be cool!
I am not a fan of pure convection cooling because until you have hot components there's no cooling. I don't like hot-running stuff, therefore a fan is required, though it doesn't usually have to be as intrusive as a Wind-Tunnel G4. A small 12V fan running on 5V or 7V is near silent and is sufficient for cubes, many video cards, and iMacs.
it wasnt much of a problem back then, but nowadays the hot-cold-hot-cold of convection cooling, or poorly fan cooled components have a tendency, and a strong one at that to break the solder connection between ICs and circuit board. (xbox360, ACER laptops, ibook g3/g4)
The Rev A-D (233mhz-333mhz) had the internal fans. The ones with 350mhz or higher don't have fans. Having a 333mhz and 500mhz indigo the only problem I found was burning discs. I usually got a media error, I would have a fan blowing on the case and shut down the mac, after that the same project would burn no problem. I also agree with the person said that said that the CRT throws off a lot of heat.
I've blown one PAV assembly in a G3/600 from excessive heat. The machine still worked, but it took a while to build up the required charge for a successful illumination of the tube and the horizontal sweep. Even once it was running, it would dim and brighten, flicker, etc. (That board has since been replaced) It's of my opinion that the convection cooling is adequate but only under strict scenarios. Correct elevation, lack of obstructions and other room temperature and environmental factors.
Upgrading the cooling system inside an iMac G3 would only prolong the life of the machine and further harden it against the many variables in airflow. I pondered installing a fan in my iMac G3, but it hasn't been booted up in a while and now the lower case has cracks, so it seems less and less likely that I should sink any major funds into it. Probably just fix the lower case and sell it.
Upgrading the cooling system inside an iMac G3 would only prolong the life of the machine and further harden it against the many variables in airflow. I pondered installing a fan in my iMac G3, but it hasn't been booted up in a while and now the lower case has cracks, so it seems less and less likely that I should sink any major funds into it. Probably just fix the lower case and sell it.
i had an imac slot load 500mhz fail from heat. I never could fix it so i trashed it.
it would power up just fine, but then after a little bit, you could see the picture pulling in on the sides of the CRT, basically the horiz sweep was starting to loose its width. then it would suddenly pull in much faster and poof. machine would shut off. resoldering every solder joint and testing every capacitors ESR didnt turn up the issue. so i junked it.
it would power up just fine, but then after a little bit, you could see the picture pulling in on the sides of the CRT, basically the horiz sweep was starting to loose its width. then it would suddenly pull in much faster and poof. machine would shut off. resoldering every solder joint and testing every capacitors ESR didnt turn up the issue. so i junked it.