my 'broken' g5 2 GHz (doesnt work with cpu fans inside) keeps 68-71 C

every mac can be recalibrated with ASD software.

[ Edited by zukow 30.05.2013 - 22:46 ]

i have 68-71°C with my PowerMac G5 @2GHz

On my frankenstein Dual 2.7MB with a replacment Dual 2.0 CPU replacement, the CPU temp is running around 70-75ish, which is at least 10C higher than temperature monitor on MacOSX is saying, if I quickly reboot back into MacOSX the temperature is not high at all, which given that the fans are not kicking in suggest that the temperature shown is too high than the actual temperture.

At least I hope so.

NAP is enabled on the G5 isn't it?

in full load my Powerbook 5,8 1,67Ghz is going up to 60°C with fans spinning like mad : )
around 45/46°C when browsing the web, IRC etc.

Compiling stuff whilst also downloading large files and browsing the web on my Powerbook 5,8 I get around 55-60 degrees centigrade. It idles around 40-45 degrees.

On my PowerMac G5 2.3Ghz I hover around 60° C on bootup and 74° C once it's on awhile.

[ Edited by realstar 03.06.2013 - 11:29 ]

Dual G4 FW800 1.42GHz runs under MOS at 42-45 ° C , under OSX 58-60 ° C . You can hear that the fan is runnig on higher rpm under MOS.

PowerBook 1.67: 40-61 degs
It dependends on which component you choose to check.

NorthBridge is allways the most Hot for me. I tryed some applications using CPU at 100% and intensive GFX usage like Quake III



[ Edited by serge 31.05.2013 - 17:33 ]

Quote:

No.

As for PowerBook temperatures, these will vary depending on the state of your hardware - the amount of dust in the fans and the quality of thermal grease conducting heat from the GPU, CPU and the NB. After replacing the original grease, the GPU should become hottest and the NB coolest (usually).

PowerMacs G5 run at full speed. PowerBooks, iBooks and Minis do not.

OSX is constantly switching the CPU frequencies, while MorphOS is running at max speed, so in the result both CPUs are getting hotter. One CPU is getting hotter than the other because the cooling fluid is flowing from one (the cold one) to the second, which gets the already warmed up fluid from the first CPU.

As the temperature is in general higher than when using OSX, the fans are running faster and producinig more noise.

If you compare two identical models with MorphOS and one is silent, while the other one is making your ears numb, then there is an issue with the cooling, the sensors or the cpu. This can be dust on cooling plates, a tollerance in sensors/cpu, a not so perfect contact of the heat pipes and the chips and of course the cooling liquid that should be replaced and the water cooling may need a clean from the inside.

So even with two fully reworked G5 running at the same speed, it is possible you never get them equal in noise output.

Geit

PS. Same of course for the FAN only versions of course.

[ Edited by geit 03.06.2013 - 11:05 ]

Geit,

actually, PowerBooks, minis, iBooks and G4 Power Macs do run at full speed, but support the NAP feature of the G4. Additionally, 1.67GHz PowerBooks support DFS2, meaning they run at half CPU clock when idle (and NAP as well).

Quote:

Uff, so it's not only me ;P

My PowerBook:
Load 59°C
UnLoad 41°C

PowerMac G5 2.7 GHz: 86°-93°, when running longer even up to 102°

@geit: Thanx for explanation. Now I know why fans under MOS run always at full speed (quite noisy). The machine is really a lot(!) faster than my G4 1.5 GHz. Watching 1080p Videos at full speed and having just 35% CPU usage is really cool. But cause of the noise I doubt the G5 will replace my G4 as my main machine. It's a pity.

I was surprised that the temperature is already 86° immediately after switching on the machine, even if ist wasn't used for hours...

pOS,
Quote:

You should consider a proper rework of your G5s cooling system.

Geit

I think the temperatur sensor on my Powerbook is a bit weird/buggy. Under full load the temp goes up to about 58C and then sometimes jumps to 75C in a second. fan is spinning and it quickly jumps back to 58C or whatever the last shown temp before the jump to 75C was. When idle it is at about 40C (± e few Cs depending on environment temp).

Zylesea,
Quote:

Well, first of all the temperature is updated in intervals, so you will not see any slow movement.

Secondly you seem to have no idea how much heat a cpu can create within a second. If you take a cpu without any cooling, put your finger on the cpu and turn the computer on for a second, your finger is most likly burned.

Geit

Quote:
I am not really that clueless abot semiconductors as you may assume and know pretty well how hot a cpu can get . The funny thing is that the jump between 58C and 75C is w/o a step inbetween while it takes a while to cool down even a _single_ more degree. As much as I know about thermodynamics and current I think I would expect an exponential function, but acually I observed a step function between 58C & 75C and from and till 58C again the function is exponential as expected.

Well, my 2xG5/2.5 GHz is much much quieter than my FW800 2xG4/1.8 GHz, I'd say, it's a quiet as my previous supersilent Pegasos. And when it's on it's 86 degrees, it's still pretty quiet...

Martin.

Quote:

@ Geit

And could you please tell how to do that properly? What tools are needed and can it be done by itself?

Thanks in advance for help.

Regards

Christoph

My Passive cooled 2.7ghz is at 86.4C when I do nothing, but when I put it under 100% load by playing a 1080P video (Which btw it can't do smoothly if you were wondering.) and it never went over 88.9c. Fans stay quiet and spin up very little.

My other LCS 2.7ghz setup has the newer revised cooler by Panasonic, and that guy sits at 84c without doing anything, and it never goes passed 86.5c under 100% load.

The spare 2.0 G5s I have will hover mid 40s.

Well, MPlayer can't play MP4 files at full speed with 100% load, but when playing avi file, with even higher bitrate, the replay is smooth at about 30-40% load, ofcourse i am talking about 1080p videos :)

And top temperature was about 88 degs, and the machine (2xG5/2.5) wass still pretty quiet. Well, i can't hear it at all, when my 2xG4/1.8 is on :)

Martin.

Quote:

@Doffo and Mark

h264 1080p is certainly doable on a 2.5 or 2.7GHz machine. It's even ok on my 2.3GHz.

What about some examples of these files that wouldn't play at full speed ?

Better make sure you enable cache in mplayer or have sufficient i/o speed of course. These files may not play fluently over a slow smbfs link (for instance... :)).


[ Edited by Fab 05.06.2013 - 06:46 ]

rms,
Quote:

I heard and saw what is required to do it, which convinced me that - if I would own a G5 with liquid cooling - I would leave that to experts.

It is not only about the knowledge. I guess everybody can remove an reattach such cooling, when he takes his time. It is more the detail work and the tools you need.

Basic plumber skills come in handy. You need to know a way to get any air from the system. All connections must be clean and fit perfect. The pipes need to be cleaned from the inside. The cpu mounted cooler need to be cleaned from the inside. You need proper material to seal everything, cooling paste and finally you need specific software to calibrate the system again. Well, this also implies that you had a custom made wrench to reach the places to unmount the entire stuff in the first place.

Same btw goes for the air cooled system. If you remove a broken fan, just replacing it will not helpl. Without running a proper recalibration the system will run the other fans still at maximum speed.

After hearing about what it takes to do it right, I would hand over the system to someone who knows what he is doing and at least did that a few times with his own systems. I am unable to do it myself.

If someone thinks he is qualified, because he dismantled and rebuild a PowerMac G4 from scratch, then he is totally wrong. The G5 systems are not only speed wise playing in another league.

Geit


[ Edited by geit 05.06.2013 - 10:27 ]

Well... I guess it's not extremely difficult to try.
Though Powermacs G5 are another world (yup!) compared with G4 (and with anything else, I suppose..) I'd rather sure to perform all operations.
I have to say I've dismounted two G5 dual 2.7 (one of them is a skeleton now!) to recover parts of one and to clean and check for leaking of the other. You need the right tools, spare parts, ASD disc for calibrate cpu and fans and a whole set of patience. Obviously, reading carefully every sort of documentation that it's possible to find online and go step by step.
Interesting thread about repairing a LCS of a dual 2.7:
http://forums.macrumors.com/showthread.php?t=1109014
Pumps for liquid cooled system (just in case...):
Swiftech 12V DC Water Cooling Pump - MCP350
Viton O-Rings to replace:
Viton O-Rings
Video about how to calibrate a G5:
Powermac G5 fan calibration
and so on.
Yes, this is not an easy operation but I would (and probabily will) do to my G5.