[Dorian Gray]

My 12-inch iBook G4 1.2 GHz has a pretty good battery life, allowing about five hours of browsing the web wirelessly with the screen at half brightness. With full CPU usage that figure halves, but that is fairly irrelevant to me because I rarely need to do something processor intensive and of long duration while on battery power. When Steve Jobs announced the switch to Intel he gave as a primary reason the performance-per-watt of Intel processors compared to PowerPC, but if performance-per-watt were everything he would have announced a swtich to ARM chips, not Intel! And indeed, for my usage performance-per-watt is not as important as low absolute power consumption (while using the battery), and high absolute performance (when connected to AC).

The Pentium M is undoubtedly a fantastic processor, but it is not as parsimonious as the hype might suggest. My girlfriend's Dell laptop with a Pentium M 725 processor (1.6 GHz) has a poorer battery life than my iBook (despite having a battery almost twice the size, although it has a bigger screen too). Interestingly, when browsing the web my iBook becomes just perceptibly warmer than when off, in contrast to the Dell which gets quite warm to the touch. However the Dell has a much more powerful graphics card (ATI Mobility Radeon X600) than my iBook, which probably accounts for some of the extra power/heat.

Anyway, I thought I'd find out how much power my iBook uses. The worst case scenario is under 100% CPU load and with the screen brightness at maximum. In this case, OS X reports that my iBook uses 22.4 watts of power. With the screen brightness reduced to minimum (but with the backlight still on) the power consumption under full load drops to 19.1 watts. However, with the CPU fairly idle (and on reduced processor performance) and the screen brightness at this low level, power consumption drops massively to 7.59 watts. Impressive! The G4 processor must use very little power while idle or close to idle. To get a better idea of how much power the CPU uses I then measured the consumption with the screen and hard disk switched off, with the CPU still close to idle. Power consumption fell to a surprising 4.98 watts! Of course the graphics card was still using some power, the memory (256 MB built-in module and 512 MB chip in the expansion socket) was using power, and the logic board in general was using some power. So I can only be certain that the 1.2 GHz G4 uses less than 4.98 watts when idle. Probably significantly less.

How does this compare with the Pentium M? Intel publishes TPD figures (similar to my maximum power above) but doesn't specify how much a Pentium M 725 uses when throttled down to 400 MHz. Wikipedia suggests 5 watts but may not be accurate. Regardless, I don't think we'll see significantly better maximum battery life with Intel processors. Absolute performance will increase (probably by a lot), but I doubt that the lowest absolute power consumption will decrease by much. In which case maximum battery life will only increase if Apple provides a larger battery (and I hope they don't take that route).

Any thoughts? Has anyone been blown away by the low power usage of the Pentium M?

[Banana]

My dell is a M; and I get maybe three hours of battery life in my normal usage, which I think is spiffy.

I can easily do my caddying wirelessly that long, which I'd imagine takes quite an amount of horsepower.

But I do think it could do better; if I'm not caddying, the time is pretty much same even with the low usage. In other words, I can't trickle battery beyond three hours even if I had screen brightness at minimum, turned off graphics on my web browser, etc. Maybe I'm doing it wrong, or Dell's battery management sucks, I dunno.

So it's just that; a spiffy performance.

Mac OS may be able to change that, though.

[ast3r3x]

Is it just the Pentium-M or the centrino setup?

[Ichiban_jay]

I think the G4 is able to use as little as 15 watts. or as much as 25-30 watts. I'm not sure of the actual number but I'm sure plenty of truly hardcore number whores we have here will know the exact numbers.

[chucker]

Originally Posted by Dorian Gray significantly better maximum battery life with Intel processors. Absolute performance will increase (probably by a lot), but I doubt that the lowest absolute power consumption will decrease by much.

Well, I think that's just the point: maintaining fairly low power usage while massively increasing performance.

Current Apple laptops, as you found yourself, already have very low power usage and batteries that sometimes last more than five hours.

Any thoughts? Has anyone been blown away by the low power usage of the Pentium M?

Note that almost all rumor sites agree that Apple won't use any current-generation Intel processor.

[Wickers]

I've been impressed by the P-M...

My LG xNote is based on the P-M and it's speed is quite acceptable for how much heat is given off.

Now, if you ask me about battery life.. .I donno, I get great battery life on my P-M (centrino) notebook but the G4/G3 arch has been designed around embedded computing and industrial PCs and most components are very low power compared respectively to intel's mobile arch. When you get that 'cool' so to speak, even a few watts can make all the difference.

More power under the hood, hell yes, we will be rockin the house with intel chips in Apple's mobile lineup... but unless they have something up their sleeves, I for one don't expect a 5 hour battery life out of new i(ntel)Books.

I also wonder how they will implement the sleep function, to which I have always admired Apple/OSX/PPC for... you can sleep your iBook between usage and can last an entire school day of use in class. With my LG, sleeping the computer just adds about an hour at most of battery life, and that hour means nothing as the computer is not usable in sleep.

This is where hibernation comes in, if Apple can pull off what I hope will happen, and instant hibernation and wakeup (or within a minute) could greatly improve the i(ntel)Book's power cycle and drain time in everyday usage.

Hibernation (for the few that might not know the difference between sleep and hibernation as it's not common in Apple hardware) is when the current state of the computer is 'imaged' and written to the hard disk. So the RAM's contents for example would be copied to disk. Then the computer is powered off completely. Upon power up, the very low level task of loading the 'image' on the disk, back into memory takes place. Finishing off with the restoration of that saved session. Sleep, on the other hand just puts the running kernel into a dormant state and powers off every component (like your hard drive and LCD) keeping power flowing to the system board and memory so as to keep the current state ready to power back up when woken.

[chucker]

God no, I really hope Apple doesn't have to resort to hibernation. Their current sleep implementation, especially with the addition of Safe Sleep, is far superior.

[faramirtook]

Originally Posted by chucker God no, I really hope Apple doesn't have to resort to hibernation. Their current sleep implementation, especially with the addition of Safe Sleep, is far superior.

Hibernation and Safe Sleep are the same. Safe Sleep just sounds cooler.

http://docs.info.apple.com/article.html?artnum=302477

[chucker]

Originally Posted by faramirtook Hibernation and Safe Sleep are the same. Safe Sleep just sounds cooler. http://docs.info.apple.com/article.html?artnum=302477

Incorrect.

Safe Sleep saves RAM to the hard drive, then goes to sleep. If the battery were to run out (with no other power source available), this would preserve memory thanks to the hard drive.

Hibernation saves RAM to the hard drive, then turns off.

The "save RAM to hard drive" process is obviously there in both cases, yes.

Why do I prefer Safe Sleep? Because it only forces the "recover RAM from hard drive" process when it has to.

[Legodude522]

I think the labeled 6 hour battery life on my 14" is true or very close when watching a movie with lowest brightness and Airport off. I always use lowest brightness whenever I'm using the battery. I do that with my Palm as well.

So I'm thinking maybe an Intel Pentium M in the iBook series and a Pentium 4 in the PowerBook series. The day that Apple uses a Celeron, is the day Apple dies.

[chucker]

Originally Posted by Legodude522 So I'm thinking maybe an Intel Pentium M in the iBook series and a Pentium 4 in the PowerBook series.

Yeowch! Bad. Bad.

Much more likely: a single-core Yonah (Intel Core Solo) for the iBook, but a dual-core (Intel Core Duo) for the PowerBook.

[MCQ]

Originally Posted by chucker Much more likely: a single-core Yonah (Intel Core Solo) for the iBook, but a dual-core (Intel Core Duo) for the PowerBook.

Bingo. That's what I'm expecting.

Legodude: Don't get wrapped up in the marketing names either, because guess what many of the single-core Yonahs may end up getting branded as?

http://www.anandtech.com/cpuchipsets...oc.aspx?i=2554

(Look to the bottom)

[kaseyha]

I haven't read the other threads on this subject, so I apologize if this has already been said, but might it not make more sense for Apple to make the first Intel based PowerBook a 64-bit laptop? This would mean they would have to wait for the second half of '06 for the Merom chips and would make sense based on the Steve's original time frame.

Also, this would seem to make it easier to get away with putting dual-core Yonahs in the iBook, from a marketing standpoint.


And, to stay on topic, while I agree that there will probably be little to no difference in actual battery life for the Intel books, the current Pentium M does seem pretty impressive power usage wise for the amount of performance it gives. The couple of Pentium M notebooks I have used had similar battery life to my iBook, but were generally faster, not counting teh snappy.

[Dorian Gray]

Originally Posted by Dorian Gray Regardless, I don't think we'll see significantly better maximum battery life with Intel processors. Absolute performance will increase (probably by a lot), but I doubt that the lowest absolute power consumption will decrease by much. In which case maximum battery life will only increase if Apple provides a larger battery (and I hope they don't take that route).

Well, three years later and the battery life of Apple's latest notebooks is still no better than the iBook (and sometimes worse). To be fair, Apple has reduced the battery capacity on the latest MacBook and MacBook Pro models.

And in stark contrast to the situation of the early noughties, these days just about every serious laptop manufacturer, from Dell to Sony, offers a couple of models with much better battery life than anything Apple can offer.

I'll give this thread another bump in 2011, perhaps.

[Swox]

But the amount of processing you can do per charge has increased vastly, hasn't it? That's got to count for something!

[Robo]

Originally Posted by Swox But the amount of processing you can do per charge has increased vastly, hasn't it? That's got to count for something!

Not to mention that the newer notebooks are thinner and lighter and are thus using smaller batteries.

The iBook was 1.35" thick and nearly 6 pounds. The new MacBook is under an inch thick and 4.5 pounds. That's a 25% reduction on both counts - hardly insignificant. And, of course, the new MacBook is way more powerful, as well. But the battery life remains the same.

Apple could make a bulky laptop (or an ultra-slow one) that got super-long battery life too, if they wanted to. It's not like Dell, HP et al. have access to some secret that Apple is oblivious to. It's more likely that Apple simply feels that 4-5 hours of battery life is enough for most users, and so they empower and shrink their laptops as they can while keeping that battery life constant.

[Mugge]

For once I find myself agreeing with our resident thinnist. The MacBook has shed so much bulk that it really makes me question the added value of the Air. And without loosing any battery life, but gaining in terms of user serviceability.

[Dave]

I was just at the store yesterday, and the Air is still noticably lighter and thinner.

[turbulentfurball]

Originally Posted by Dorian Gray Well, three years later and the battery life of Apple's latest notebooks is still no better than the iBook (and sometimes worse). To be fair, Apple has reduced the battery capacity on the latest MacBook and MacBook Pro models. And in stark contrast to the situation of the early noughties, these days just about every serious laptop manufacturer, from Dell to Sony, offers a couple of models with much better battery life than anything Apple can offer. I'll give this thread another bump in 2011, perhaps.

*bump*

2013 MacBook Air Dorian?

[Dorian Gray]

Oh, recently things have improved tremendously. The Airs are unbelievably parsimonious with power, and their batteries have creeped up in capacity too. The result is very impressive.

My own late-2013 13-inch MacBook Pro with Retina display has a staggering battery life:



I’d still love to know what a 2014-era PowerPC PowerBook would have been like – maybe even better, even more ARM-like for low-intensity usage? – but I’m satisfied with the way things have gone in the last couple of years. For sure.

[turbulentfurball]

Originally Posted by Dorian Gray

I have the same MacBook Pro. I don't get that kind of battery life playing Civ 5...

[Dorian Gray]

I bet you don’t. Which is one reason we still need progress.

Doing stuff like this – surfing the web, typing, generally farting about with the display at six bars of brightness – I get about 10 hours out of the battery, or an hour per 10 % of battery capacity (that’s how I think of it).

[Partial]

I routinely get about 8 hours out of the same 13" rMBP haswell. It is the greatest computer ever made. I legitimately believe that. It is my favorite electronic item ever. So light, yet so fast and beautiful!

[Dorian Gray]

Originally Posted by Partial I routinely get about 8 hours out of the same 13" rMBP haswell. It is the greatest computer ever made. I legitimately believe that.

I’d certainly agree it’s in the running for the best computer ever made. But I still cannot get as excited about it as I was about my iBook back in the day, or even my original unibody MacBook Pro (a true leap in quality in every way).

The iBook was just leagues ahead of all its competitors – ironically while Apple’s market share was minuscule, something I never understood then – while today there are manufacturers who at least try, a little, to deliver on overall quality. Don’t get me wrong, no-one makes anything like the MacBook Pro, but the gap isn’t as vast as it was with the original white iBook.

Also, the PC suffers from creeping irrelevance. The action is in more-mobile devices now. While that doesn’t detract from the qualities of the MacBook Pro itself, it does make it a little less exciting.