CPU nap ?

[SPeedY_B]

I've been trying to find some information reagarding CPU napping, but haven't been very sucessful.

I have a Dual 1.25 G4 PowerMac (MDD, FW800) and have read different things regarding enabling the nap option. Some say it should only be used for G5 chips, some say it makes a big differece in temps (I tried it shortly, my temps dropped almost 20 degrees) but also causes stability issues, others say it's simply the best thing since sliced bread.

So is it safe to leave on? or should it just be left alone?

 

[crazzyeddie]

I've been trying to find some information reagarding CPU napping, but haven't been very sucessful.

I have a Dual 1.25 G4 PowerMac (MDD, FW800) and have read different things regarding enabling the nap option. Some say it should only be used for G5 chips, some say it makes a big differece in temps (I tried it shortly, my temps dropped almost 20 degrees) but also causes stability issues, others say it's simply the best thing since sliced bread.

So is it safe to leave on? or should it just be left alone?

Also, what on earth does this actually do? I know it has something to do with power usage... but do any of you Mac techs know exactly what its purpose is?

 

[SPeedY_B]

It puts the CPU to sleep for short periods of time (ie: milliseconds) when it's not doing anything, in effect using less power and bringing the temprature down significantly.

I just want to know if it's ok to use permenantly on G4's

 

[reaper]

just curious... why are you interested in this feature? i have the same machine and have never had a problem with the temp inside the case or needing to nap the processors.

- reaper

 

[crazzyeddie]

I just want to know if it's ok to use permenantly on G4's

Well Apple enables it by default... so I would think it would be safe to use...

 

[naodx]

Actually nap mode isn't turned on by default on G4's, it is I believe on by default for G5's. (Not sure on that as I don't own one.)

I tried this on my machine machine and it would lock up randomly, and when trying to power down.

There have been several reports on this issue with G4's on www.xlr8yourmac.com

 

[crazzyeddie]

Actually nap mode isn't turned on by default on G4's, it is I believe on by default for G5's. (Not sure on that as I don't own one.)

I tried this on my machine machine and it would lock up randomly, and when trying to power down.

There have been several reports on this issue with G4's on www.xlr8yourmac.com

It is on all Apple portables... maybe the desktop chips aren't designed to use it, or something else like the PMU isnt designed for the constant power changes?

 

[naodx]

Not to contradict you, as my Powerbook is a 667MHz model, but are you confusing nap mode under energy saver with the nap node under System Preferences/Other/Hardware?

Like I said, I don't own a newer powerbook, or a G5 for that matter, but the only way that I knew/know that the Hardware option is installed, is by installing the Developers tools. More precisely the Hardware option is part of CHUD.

Is this getting installed by default now?

One of the things this option did (at least for Desktop G4 owners), is allowed the processors to run much cooler. Mine went from 59.x C to around 38.x or so. The drawback was that the OS became very unstable and would lockup at random and when trying to shutdown.

There have been mixed reports about using this nap mode by various G4 users, on www.xlr8yourmac.com

 

[crazzyeddie]

Not to contradict you, as my Powerbook is a 667MHz model, but are you confusing nap mode under energy saver with the nap node under System Preferences/Other/Hardware?

Like I said, I don't own a newer powerbook, or a G5 for that matter, but the only way that I knew/know that the Hardware option is installed, is by installing the Developers tools. More precisely the Hardware option is part of CHUD.

Is this getting installed by default now?

When I installed the CHUD tools, it was on already. I have a 1ghz Titanium.. which i know runs alot hotter than the 667 did, maybe that was a new feature/default then?

 

[naodx]

Could very well have be.

Maybe it is a problem in particular with the series # for the G4 chips in the desktop models???

 

[crazzyeddie]

Could very well have be.

Maybe it is a problem in particular with the series # for the G4 chips in the desktop models???

Could be that Motorola didn't deem this a necessary feature until the chips were really starting to be pushed for the extra mhz (when Apple started looking to IBM for new processors).