[mrgreen4242]

I have yet to figure out why there aren't any dual CPU laptops. Seems to me that turning off one of the cpu's would be a very effective powersaving technique. (would it draw significantly more power than a single cpu syte, of the same speed??). Could easily just disable the second proccess when not on AC power (user level choice, of course)... And it's not like 17" dual cpu laptop customers are usually worried about battery longevity anyways.

There's all the obvious things like size/wieght/cost. But, really, those 17" powerbooks are HUGE, and the small weight increase from the extra CPU and the required parts couldn't be THAT much. (Did I mention those 17" powerbooks are already FREAKING huge???)

For price, well, again, a 17" powerbook is already around $3000. And it's a generation old, so seems like you could offer a 2xG4-1.33ghz for the same price in the near future. From what I have read the dual G4's are still alot faster than a single (faster per cpu speed) G5. (for MP aware tasks, of course).

Also seems like it'd be a big seller. No need to have a PowerMac at home and a PowerBook on the road. Having a second display, a bluetooth keyb/mouse, and an extra firewire drive at home would be enough for most people.

So, is there any reason why you CAN'T have a dual CPU laptop? Some technical problem I am not aware of?

-Rob

[Maflynn]

First of all do a search on this forum, I believe this topic has been covered.

Secondly a few issues came to mind rather quickly which of course doesn't mean apple will/cannot produce one.

You mentioned battery life and those people of the 17" don't care about battery life. well I own a 15" and I do care, and from other posts about how short a battery last this is not an uncommon issue. A second cpu, support circuitry and the additional fans would suck the battery dry in no time.

Heat - this is probably that largest issue facing a dual cpu laptop. The Pb would be red hot with a 2nd cpu, again see how many threads there are about how hot their respective laptops get.

engineering - it would be very difficult to squeeze in another cpu in an already cramp enclosure and keep the air flow (the aforementioned heat issue)

Cost - you said it yourself if the 17" is going for 3,000 well how much more would a dual would go for, you can bet it would be more then the current cost and probably too much to justify the R&D & Mfg.

Demographics - know your customers, how many PB users truly would need a dual CPU and can that pool of customers offset the design and manufacturing costs.

So I'm sure there are many more opinions for and against but those are mine fwiw.

Mike

[iREZ]

I'm going to agree with green on this one.

a 15" and a 17" are two different computers. I have a few friends that have the 17" and rarely do they use it far from an outlet, it's their only computer and they use it solely. So I agree that even a 1-1/2 hr charge battery would be ok for such a computer.

Heat is another issue you mention, but the G5's are going to be just as blazing when it comes to cooling them down, so this is very possible to do with a dual what is inevitably going to be done in a single G5.

17" isn't cramped at all, the 12" now thats cramped, I'm sure its very possible to add another cpu in a 17" if they thicken the thing up from 1" to the same thickness of the 12" (which I dont know, nor do I care).

Cost could be a few hundred bux more, too much you say but I know for a fact my friends would sell their computers in a second and put up another 2 to 3 hundred bux for duallies in a PB. As for how many users would want this, I'm not too sure and have to aggree with Maflynn that it might not be too many seeing how people would rather get a dual G5 tower instead.

Dual G4 Powerbooks aren't that bad an idea in my opinion, but for the long run I think a G5 Powerbook would make more sense seeing how software will be made precisely for G5 units in a year or two.

[mrgreen4242]

Originally posted by Maflynn:
First of all do a search on this forum, I believe this topic has been covered.

oops. Shrug, never hurts to rehash things in a new light. If someone is tired of reading/posting abotu this topic, feel free to move along .

Secondly a few issues came to mind rather quickly which of course doesn't mean apple will/cannot produce one.

You mentioned battery life and those people of the 17" don't care about battery life. well I own a 15" and I do care, and from other posts about how short a battery last this is not an uncommon issue. A second cpu, support circuitry and the additional fans would suck the battery dry in no time.

Ok, not be critical here, but you're comparing 2 unlike things here (hate to use apples and oranges, since they're both apples ;-). A 15" laptop is still in the realm of portablity, whereas, imo, a 17" just isn't. I think that the 17"'s are more desktop replacements for people who need to have the saem computer at home and work, or some other similar situation. That aside, as I said, it looks like to me that 17" PB users are less concerned about battery life than they are about pwer, performance, and, clearly, screen size. Those who choose battery life and portability go for the 12 and 15" models, as YOU clearly did. Also, I am of course not suggesting that all 17" models be dual cpu, and that people can make thier own choices based on what is available to them and what best fits thier needs. Lastly, I would think that you could disable a second CPU and its support systems and have minimal extra power draw. Maybe I am wrong.

Heat - this is probably that largest issue facing a dual cpu laptop. The Pb would be red hot with a 2nd cpu, again see how many threads there are about how hot their respective laptops get.

Agreed, heat would be the most difficult issue. It is one that could be dealt with, however. There has been alot of work with liquid cooled laptops lately, just as one possible direction. (also, see below regarding the extra space inside a 17" compared to a 15" PB).

engineering - it would be very difficult to squeeze in another cpu in an already cramp enclosure and keep the air flow (the aforementioned heat issue)

Airflow/heat aside, I think that space is a non-issue. The area inside a 17" PB is abotu 25% greater than in a 15", yet they manage to squeeze all the same features in (with the difference of a 80mhz faster machine, which I doubt requires that much more cooling apperatus.

Cost - you said it yourself if the 17" is going for 3,000 well how much more would a dual would go for, you can bet it would be more then the current cost and probably too much to justify the R&D & Mfg.

I also mentioned that the current $3k PB is a generation old. It is going to come down in price significantly, and soon. Furter more, all of the system design is there for dual cpu systems, it is amatter of adapting it for laptop use. Much easier task then creating an entire new system reference.

Demographics - know your customers, how many PB users truly would need a dual CPU and can that pool of customers offset the design and manufacturing costs.

I would guess all of the PB users who have dual PM G4's at home are in that demographic. Which, from what I can tell, is an aweful lot of them.

So I'm sure there are many more opinions for and against but those are mine fwiw.

Mike

Thanks for replying, it's always helpful to see other sides of a topiic.

Rob

*A vote for BUSH 2004 is a vote for DRAFT 2005*

[ibook_steve]

(Electrical engineer hat on...)

One thing that nobody has mentioned against this good, although highly unlikely or possible, idea is board space. Yeah, you could get around heat and airflow with a z height increase (something Apple will *never* do: "Introducing our now not quite 1-inch think super hot dual CPU Powerbook), but where the heck are you going to put that CPU? Have you looked at a Powerbook logic board lately? Of any size? It's literally packed. There is no room whatsoever for another CPU let alone any extra supporting "traffic cop" chips required for choosing which CPU is in control of the bus at the time (a process called bus snooping). And forget about a processor daughter card. Besides the extra height, I don't think Apple would ever go back to a design that people could upgrade. Nice dream, but, at least for the immediate future, it ain't gonna happen.

Steve

[Maflynn]

Originally posted by ibook_steve:
(Electrical engineer hat on...)

One thing that nobody has mentioned against this good, although highly unlikely or possible, idea is board space.

Actually I did but probably been a little more clear.

engineering - it would be very difficult to squeeze in another cpu in an already cramp enclosure and keep the air flow (the aforementioned heat issue)

As for mrgreen's response
Your right, I didn't mean to muddy the water with the 15 vs 17" pbs. But let me say this. A 17"pb is portable so you need to take into consideration heat, and battery life, weight and size. It may not make as many trips as a 15 or a 12" pb but people still take it on trips.

I have to disagree with your assertion

I would guess all of the PB users who have dual PM G4's at home are in that demographic. Which, from what I can tell, is an aweful lot of them.

I don't think you can make the leap that most/all of the current dual powermac users would have a need for a dual cpu PB never mind actually purchase one. if they could afford it that is - purchasing a dual PM and then going and spending 3,000+ for a dual PB.

I really don't see a market that could affored or justify this baby. would I want one, probably as long as the battery lasted more then 5 minutes and it wasn't beast to lug around.

My basic premise is it will be expensive for Apple (or any company) to research, design, and implement such a computer, for what would be almost certainly a very limited audience. There is some serious engineering hoops to jump through for what I would think a small segment of customers. Apple would not make any money on the puppy.

As they say fwiw that where I stand.

Regards
Mike

[mrgreen4242]

Originally posted by Maflynn:
Actually I did but probably been a little more clear.





As for mrgreen's response
Your right, I didn't mean to muddy the water with the 15 vs 17" pbs. But let me say this. A 17"pb is portable so you need to take into consideration heat, and battery life, weight and size. It may not make as many trips as a 15 or a 12" pb but people still take it on trips.

I have to disagree with your assertion


I don't think you can make the leap that most/all of the current dual powermac users would have a need for a dual cpu PB never mind actually purchase one. if they could afford it that is - purchasing a dual PM and then going and spending 3,000+ for a dual PB.

I really don't see a market that could affored or justify this baby. would I want one, probably as long as the battery lasted more then 5 minutes and it wasn't beast to lug around.

My basic premise is it will be expensive for Apple (or any company) to research, design, and implement such a computer, for what would be almost certainly a very limited audience. There is some serious engineering hoops to jump through for what I would think a small segment of customers. Apple would not make any money on the puppy.

As they say fwiw that where I stand.

Regards
Mike

Agreed that it would be an expensive undertaking for anyone, but I do think that it would be one that could payoff.

Not all powermac users would want a dual cpu laptop. But I think that alot of people who have a fast desktop at home and who ALSO have a powerbook would be interested in combining the two even more effectively.

All of that said, this definately isn't the time that they will be doing any research towards building a dual cpu latop, as htey are switching thier desktop lines over to the G5 and the powerbook doesn't even have a single G5 yet. I'm just speculating

I still think that it is doable, and we might see it in a few years time...

[Pierre B.]

Originally posted by mrgreen4242:
I have yet to figure out why there aren't any dual CPU laptops.

No need for dual CPU if the dual core G4 comes into light. Motorola has in its roadmap a much promissing chip, that should be ready this year or the beginning of next year.

In brief, it is a classic G4, capable of going up to 2 GHz and dissipating 25W at 1.5 GHz, but it has two cores and system integration on it: DDRI and DDRII, RapidIO.

[The Placid Casual]

Originally posted by Pierre B.:
No need for dual CPU if the dual core G4 comes into light. Motorola has in its roadmap a much promissing chip, that should be ready this year or the beginning of next year.

In brief, it is a classic G4, capable of going up to 2 GHz and dissipating 25W at 1.5 GHz, but it has two cores and system integration on it: DDRI and DDRII, RapidIO.

Vapour my friend, vapour.

[cdhostage]

Yah, this topic's been beaten to death. I even participated in the dual G4 Powerbook threads (I called my idea the DiamondBook, I think - the best way to cool the thing would be a solid diamond chassis built atom-by-atom I don't remember what I said).

It would be like my roommate's DELL which sounds like a hairdryer, only whinier. It has to seriously degrade performance in order to have any battery life, that is, if you unplug it, it MUST slow down or people would sue Dell for selling 30min laptops. And the performance sucks normally, and halves when you take itt away from the plug.

Tangent over.
I would be very happy with a dual processor Macintosh laptop, and would be happy with it being the current 17 inches across as well as an inch and a half thick and weighing ten pounds. I don't mind it being big as long as it still fits in a standard briefcase and doesn't burn my knees.

[mrgreen4242]

Originally posted by cdhostage:
Yah, this topic's been beaten to death. I even participated in the dual G4 Powerbook threads (I called my idea the DiamondBook, I think - the best way to cool the thing would be a solid diamond chassis built atom-by-atom I don't remember what I said).

It would be like my roommate's DELL which sounds like a hairdryer, only whinier. It has to seriously degrade performance in order to have any battery life, that is, if you unplug it, it MUST slow down or people would sue Dell for selling 30min laptops. And the performance sucks normally, and halves when you take itt away from the plug.

Tangent over.
I would be very happy with a dual processor Macintosh laptop, and would be happy with it being the current 17 inches across as well as an inch and a half thick and weighing ten pounds. I don't mind it being big as long as it still fits in a standard briefcase and doesn't burn my knees.

Ya I that's more or less what I was envisioning... A 17" machine that was a little bigger/heavier than what we have now, and that just turned off the second CPU (as kicked the other cpu into a powersaving mode as well) when you were working from battery power (of course yo could manually turn it on, and get your 30 minutes of uber power). Just the ide would be to tote it from office to home to a hotel for a business conference to your buddies place for a little lan party, or whatever... not so much use it on the train/plain/automobile.

Also, just a totally random thought, but could you improve cooling by switching the active cpu every now and again (when only one cpu was active that it)?

Rob

[rag on a muffin]

i just wanted to add that the G5 does not get that hot, they just put a whopper heat synch on it to keep it as quiet as possible. I'm sure they will never release a dual processor because they could make up for the speed by upping the processor speed. if people really need speed at work an at home, buy a firewire, and boot up from that, or make a petition to make a G5 cube.

[KraziKid]

Originally posted by rag on a muffin:
i just wanted to add that the G5 does not get that hot, they just put a whopper heat synch on it to keep it as quiet as possible. I'm sure they will never release a dual processor because they could make up for the speed by upping the processor speed. if people really need speed at work an at home, buy a firewire, and boot up from that, or make a petition to make a G5 cube.

Look at the maximum heat output of the G5, not just the average which is what IBM releases. The G5 gets decently warm, and this is the reason for the massive heatsink, and numerous fans. Along with the reason for the tornado cooling system in the Xserve G5, even thought those are the 90 nm process versus 130 nm.

[rag on a muffin]

you could put it in a laptop, but it would sound like a geforce fx 5600.(i hope i got that right)

[Pierre B.]

Originally posted by The Placid Casual:
Vapour my friend, vapour.

Quite possible, given Motorola's track on these things. But... do you know something or are you assuming based on common sense?