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Thumannator · Jul 19, 2002, 11:56 AM

I have been waiting for some utility to come out to support reading and displaying the temperature of the processors in the latest PowerBooks. Doing some research yesterday, I am now led to believe that the G4 7451 does not have the temperature probe built into it anymore. I cannot remember where I read this actually. I think it was at Version Tracker. The author of "Thermo In Dock" was defending why his app does not work on the latest G4s.

Despite the apparent lack of the temp probe, I figure there must still be something reading the temperature. How else does my PB know when to turn the fan(s) on? Does anyone know how to get a proper temp measurement? I have yet to find an available utility that can do it, and no idea where to poke around in the system to find out.

Thanks

seanyepez · Jul 20, 2002, 03:42 AM

The fans automatically turn on to their first-stage speed based on CPU usage. The second-stage, loud fan speed is only enabled when CPU temperature gets too high.

maceye · Jul 22, 2002, 03:21 AM

So if the really loud fan only comes on when the system is too hot, it must have some sort of temp. gauge. Is there a utility that can tap this gauge for data? (Also, doesn't the Ti DVI have 3 fan speeds? I am pretty sure that I have quiet, medium and 777 takeoff fan speeds on my Ti DVI).

gorickey · Jul 22, 2002, 10:33 AM

Not sure about 3 fan speeds, I've heard of only 2 and that is on the Ti DVI 800...the DVI 667 I've personally heard only one setting since I've had it.

euphras · Jul 22, 2002, 11:04 AM

The 667 DVI has at least also 2 fan speeds! The hairdryer mode comes on if you do gaming

The 800 has two distinct fans, which are regulated in a cascade like manner. Thats maybe the cause why it sounds like three different fan speeds.

Pat

fmalloy · Jul 22, 2002, 08:57 PM

I've heard (dunno if it's true) that there is a temperature probe on the G4, but that a temperature API does not exist in OS X, so developers cannot access it. I'm pretty sure I got the temperature of my Ti 500 using Jeremy Kezer's control strip temp utility in OS 9. I'm too lazy to reboot to 9; perhaps someone can confirm?

fmalloy · Jul 22, 2002, 08:58 PM

I've heard (dunno if it's true) that there is a temperature probe on the G4, but that a temperature API does not exist in OS X, so developers cannot access it. I'm pretty sure I got the temperature of my Ti 500 using Jeremy Kezer's control strip temp utility in OS 9. I'm too lazy to reboot to 9; perhaps someone can confirm?

Thumannator · Jul 23, 2002, 05:12 PM

I am not convinced that the CPU fan comes on based on CPU usage. Why? Well, I typically run the Distributed.net RC5-64 client on my PB 800. This app is real good about kicking the fan to its highest (second) speed. However, when I stop running the app, the fan remains on for a couple minutes afterward. This seems to indicated to me that the fan comes on based on a temperature threshold. By that, I mean that when a certain temp is reached, the fan turns on and will stay on until the temp drops back below a certain level. So, there has got to be something that is monitoring the temp, so there has to be a way to find out what the CPU temp is.

The RC5-64 client is the primary reason I want to determine the temperature. I do not want to "over-cook" my processor (though I realize Apple probably built in means to prevent this). I am really just curious because my old iMac will get up to about 117 F when it is crunching data. Well, that is on its new processor (a 466). Back when it had its original 233, the temp would get up to something like 147 F, I think. It has been a while since I swapped processors, so I cannot remember exactly.

I will try out Jeremy Kezer's control strip module in OS 9. However, his documentation doesn't seem to indicate that the module supports G4 processors. Still, I am willing to give it a shot.

PowerPC · Jul 23, 2002, 06:59 PM

<blockquote>quote:<hr />Originally posted by Thumannator:
I have been waiting for some utility to come out to support reading and displaying the temperature of the processors in the latest PowerBooks. Doing some research yesterday, I am now led to believe that the G4 7451 does not have the temperature probe built into it anymore. I cannot remember where I read this actually. I think it was at Version Tracker. The author of "Thermo In Dock" was defending why his app does not work on the latest G4s.

Despite the apparent lack of the temp probe, I figure there must still be something reading the temperature. How else does my PB know when to turn the fan(s) on? Does anyone know how to get a proper temp measurement? I have yet to find an available utility that can do it, and no idea where to poke around in the system to find out.

Thanks<hr /></blockquote>DVI's use the 7455 G4 <img border="0" title="" alt="[Wink]" src="wink.gif" />

oeyvind · Jul 23, 2002, 08:01 PM

Yes, XPC7451 for 550/667 VGA, and XPC7455 for 667/800 DVI

Musti · Jul 25, 2002, 12:45 AM

<blockquote>quote:<hr />Originally posted by oeyvind:
Yes, XPC7451 for 550/667 VGA, and XPC7455 for 667/800 DVI<hr /></blockquote>umm, no. it is actually MPC 7451 for DVI.

oeyvind · Jul 25, 2002, 01:54 AM

<blockquote>quote:<hr />Originally posted by Musti:
 <blockquote>quote:<hr />Originally posted by oeyvind:
Yes, XPC7451 for 550/667 VGA, and XPC7455 for 667/800 DVI<hr /></blockquote>umm, no. it is actually MPC 7451 for DVI.<hr /></blockquote>No, it's XPC7455 in the DVI PowerBook, as shown in barashi at <a href="http://www.MedicalMac.com" target="_blank">www.MedicalMac.com</a> and <a href="http://www.suyama.co.jp" target="_blank">www.suyama.co.jp</a>

<a href="http://www.medicalmac.com/mac94.html" target="_blank">http://www.medicalmac.com/mac94.html</a>
<a href="http://www.medicalmac.com/mac95.html" target="_blank">http://www.medicalmac.com/mac95.html</a>
<a href="http://www.suyama.co.jp/past62.html" target="_blank">http://www.suyama.co.jp/past62.html</a>

And also using Reggie.app (part of CHUD kit), this is reading from my 667 DVI:

<img src="http://home.pacific.net.sg/~oeyvind/ext/reggie.png" alt=" - " />

[ 07-25-2002, 01:55 AM: Message edited by: oeyvind ]

Musti · Jul 25, 2002, 01:57 PM

<blockquote>quote:<hr />Originally posted by oeyvind:
 <blockquote>quote:<hr />Originally posted by Musti:
 <blockquote>quote:<hr />Originally posted by oeyvind:
Yes, XPC7451 for 550/667 VGA, and XPC7455 for 667/800 DVI<hr /></blockquote>umm, no. it is actually MPC 7451 for DVI.<hr /></blockquote>No, it's XPC7455 in the DVI PowerBook, as shown in barashi at <a href="http://www.MedicalMac.com" target="_blank">www.MedicalMac.com</a> and <a href="http://www.suyama.co.jp" target="_blank">www.suyama.co.jp</a>

<a href="http://www.medicalmac.com/mac94.html" target="_blank">http://www.medicalmac.com/mac94.html</a>
<a href="http://www.medicalmac.com/mac95.html" target="_blank">http://www.medicalmac.com/mac95.html</a>
<a href="http://www.suyama.co.jp/past62.html" target="_blank">http://www.suyama.co.jp/past62.html</a>

And also using Reggie.app (part of CHUD kit), this is reading from my 667 DVI:

<hr /></blockquote>i was about to say "OK, you beat me into it", but...

please take a look at
<a href="http://e-www.motorola.com/webapp/sps/site/taxonomy.jsp?nodeId=03M943030450467M98653" target="_blank">http://e-www.motorola.com/webapp/sps/site/taxonomy.jsp?nodeId=03M943030450467M98653</a>

and tell me if you can see a 667 MHz option for MPC 7455.

oeyvind · Jul 25, 2002, 07:05 PM

<blockquote>quote:<hr />Originally posted by Musti:
please take a look at
<a href="http://e-www.motorola.com/webapp/sps/site/taxonomy.jsp?nodeId=03M943030450467M98653" target="_blank">http://e-www.motorola.com/webapp/sps/site/taxonomy.jsp?nodeId=03M943030450467M98653</a>

and tell me if you can see a 667 MHz option for MPC 7455.<hr /></blockquote>Well, look at the page you sent again (carefully), there's no rev 2.1 at all (you only see Rev 2.0)... the XPC7455 in PowerBook DVI is of Rev 2.1, in the 667 DVI and also 800 DVI.

Musti · Jul 25, 2002, 08:24 PM

hmm...OK, then. i can only say we use the latest processor from MOT, and for that i am happy...oh, i think it is called Apollo or something, and it is the processor used in the quicksilver models, too.

ps. i still have doubts about this, on one site i read the processor inside is 7455, on everymac.com it is labeled as 7451. now you say it is 7455. OK, OK. i'll stop.