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Dewaine · Feb 25, 2006, 01:47 AM

I have a rev b, iMac G5, 2.0ghz, 2 gig ram......

love it....

But, it gets hot. It seems to be a problem with all G5, and more so with the iMac. How hot? Normal load around 145 F (mid 50-60 C ), heavy load 180-200 F+

I came from WinTel side and had at one time built a high powered AMD with a high powered graphics card. It ran hot, but I just took the side of the tower off and left it open and it worked great. I can't do that with an iMac. But has anyone drilled holes in the back? Seems like that would allow more airflow and therefore help the processor, disk and graphics card run cooler.

So, if you have drilled holes, cut slots...etc and it has helped I would like to know what you did and how much it helped. I am perfectly willing to hack and slash the case. I am more of a function over appearence guy, and this would be the back anyway.

Thanks!

mduell · Feb 25, 2006, 02:56 AM

It gets hot... so? It the heat causing it to crash or some other adverse effect?
I'd let it cook.

rparke1 · Feb 25, 2006, 08:49 PM

besides, if you did in fact dril, cut whatever holes into the back, more dust would get into your computer and than ya know what happens

Dewaine · Feb 26, 2006, 12:02 PM

No crashes, but heat can damage CPU's, etc and cause hardware failure sooner than if temps are kept lower. And the various forums on the net are full of problems with iMac's overheating. I think it is smarter to fix a problem before real damage happens. Most of the problems were rev A, but the others seem to have issues as well. It just seems to me that a 180-200 F is a bit much when simply using Garageband (no other apps open). And yes I have re-set the power board several times.

I know the dust issue, I have opened up Wintels to allow air flow and seen how quickly dust collects. But I would simply use a blower once a week to keep things clean.

Bottom line is I was wondering if anyone else had tried such a thing.

Dewaine · Mar 12, 2006, 10:06 PM

In case anyone would be interested the site below has a mod for the heat issue. I'm not going to do it, but it is a solution to the problem. There are many threads on the Apple forums on the heat problems with G5 iMacs. Bottom line is most just learn to live with it. Many have hardware failures after 6 months or so because of it. From what I understand the Rev C G5' s have a different fan and baffle system than A or B.

http://www.xlr8yourmac.com/systems/i...oling_fan.html

Tuoder · Mar 13, 2006, 07:13 AM

If you screw a fan into the back and are worried about dust, you may want to try buying panty hose, (yes, I am serious) and cutting a square out that is just a little bigger than th fan and putting that layeer between the fan and the iMac. There will be no dust.

If you would prefer a less "ghetto" approach you could always buy a fan filter.

http://www.overclockers.com.au/article.php?id=141962

They seem to go for 2-5 bucks. (assuming 120mm)

imitchellg5 · Mar 13, 2006, 06:10 PM

I think Apple meant for the G5 to run hot. The inside is aluminum so it isn't like it will melt. And Apple advises about drilling holes and such. The iMac is cooled with a convection current, so holes could disrupt that.

Tuoder · Mar 14, 2006, 08:28 AM

Originally Posted by imitchellg5

I think Apple meant for the G5 to run hot. The inside is aluminum so it isn't like it will melt. And Apple advises about drilling holes and such. The iMac is cooled with a convection current, so holes could disrupt that.

I have a tendency to think that the only reason Apple chose convection cooling was for fanless (and therefore nearly silent) operation. Furthermore, they are running too hot for the (possibly out-of-spec) capacitors on the midplane logic board. I think that fan cooling would work better than simple convection. People use to mod iMac G3s (which also use convection cooling) with (a) fan(s) so that they could replace the small, 5400-rpm HDD with a bigger, hotter, 7200-rpm drive. If he doesn't mind the noise, and personally, I would mind blown capacitors more, then I think that it would be a good move to preempt the problem.

You may consider figuring out a way to blow air into the bottom and out the top, working with convection instead of without it. This may also allow you to sometimes turn the fan off.

packetattack · Mar 16, 2006, 12:32 AM

I have to say I'm surprised that more Mac lovers have not taken a page from the overclocked gamers and water(or other liquid) cooled their DualG5s etc. There has been alot of work done on silently cooling PCs ranging from 500 watt fanless PSUs to copperblocks and passive cooling towers. And stuff inbetween. Now if someone wants to *donate* a dual G5, Intel Mac to the cause, I would have happy to test it all

MikeS
hackamac.packetattack.com

goMac · Mar 16, 2006, 11:39 PM

I would not mess with the cooling system. Apple has spend a lot of time designing it and perfecting the airflow. There is a really nice airflow system in those things.

Most of the Dual G5's are already watercooled (they come that way from Apple).

greenfairy1968 · Mar 18, 2006, 04:51 AM

Okay, check this out: This is the almighty underground always banne cash68. Try it. Try it without improved fan speeds. Try it until you're stable. Try it until OSX is running okay for you. After all , you're not the mofo who's going to get 13k for booting OSX on an intel mac.

Anyways. Absinthe is cool. I highly encourage you to tehck it out. It's more than I asked for. It's really cool. www.alandia.de I had good experience with them.

- Rob

greenfairy1968 · Mar 18, 2006, 05:01 AM

Drill holes. More air= beteter. The more you can ge to cool your overclocked illegit CPU the better. Take off the back half and put ona fan. Use something from www.performance-pcs.com. They'll light up and give you a good time.

ReggieX · Mar 18, 2006, 11:20 PM

Originally Posted by packetattack

I have to say I'm surprised that more Mac lovers have not taken a page from the overclocked gamers and water(or other liquid) cooled their DualG5s etc

Go to www.XLR8yourmac.com, there are a few mods out there. Mostly PC folks can do it because the individual components are easier to buy, so if you blow one CPU, you can just go get a replacement. I'm sure as hell not going to risk destroying a $3000 machine.

goMac · Mar 19, 2006, 05:12 PM

Originally Posted by greenfairy1968

Drill holes. More air= beteter. The more you can ge to cool your overclocked illegit CPU the better. Take off the back half and put ona fan. Use something from www.performance-pcs.com. They'll light up and give you a good time.

I'm not sure why Cash thought anyone would take hardware modding advice from the drunk guy...

Grrr · Mar 21, 2006, 08:35 AM

Originally Posted by mduell

It gets hot... so? It the heat causing it to crash or some other adverse effect?
I'd let it cook.

Thats just what I did.. Let it cook. And sure enough my G5 iMac cooked itself. And required a whole new mobo at 10 months old. Caps in the graphics gubbins were kaput.