Will the next Powerbook G4 have true DDR implementation?
I am currently looking into buying a 17" Powerbook. Rumour has it that Apple may revise their Powerbook-lineup sometime early next year with the last generation G4-processors to go in the pro-portable line. What do you people know (or expect) in regards to coming G4-processors from Motorola? Some claim that the next portable G4 will have a 200MHz system buss, allowing DDR 400 memories to be utilized. If so, do you think that this processor will still be "strangled" like the current G4/DDR333 implementation or will it finally sport a true DDR-compatible interface?
I think it would be worth the few months of wait if I could then get an unfethered version of the G4-processor and that that would increase the long-livety of my future machine substantially. Your thoughts and advice on the matter would be greatly appreciated!
I think it would be worth the few months of wait if I could then get an unfethered version of the G4-processor and that that would increase the long-livety of my future machine substantially. Your thoughts and advice on the matter would be greatly appreciated!
Comments
Now if a new improved G4 came out with an independant memory interface to DDR ram of any speed it would be a very nice improvement. If the complement of I/O was DDR memory, a Hypertransport interface, and maybe the system I/O we would have a potentially awsome upgrade. There are how ever no indication that such a chip is coming from Motorola.
The issue becomes is there enough of a performance increase with the current chip to justify a revision to a 200 MHz bus. I would have to say no especially relative to the performance increase we are seeing every where else. So I think an improved G4 is in order or a complete replacement for that chip.
The bigger possibility is a complete replacement for the G4 from IBM, desinged especially for portables. But I think that is a year or two off.
Dave
Originally posted by KANE
I am currently looking into buying a 17" Powerbook. Rumour has it that Apple may revise their Powerbook-lineup sometime early next year with the last generation G4-processors to go in the pro-portable line. What do you people know (or expect) in regards to coming G4-processors from Motorola? Some claim that the next portable G4 will have a 200MHz system buss, allowing DDR 400 memories to be utilized. If so, do you think that this processor will still be "strangled" like the current G4/DDR333 implementation or will it finally sport a true DDR-compatible interface?
I think it would be worth the few months of wait if I could then get an unfethered version of the G4-processor and that that would increase the long-livety of my future machine substantially. Your thoughts and advice on the matter would be greatly appreciated!
Dont expect any new cpu's from Moto targeted at Apple. The new chip company will be struggling with their embedded customers to turn a profit.
Originally posted by KANE
I am currently looking into buying a 17" Powerbook. Rumour has it that Apple may revise their Powerbook-lineup sometime early next year with the last generation G4-processors to go in the pro-portable line. What do you people know (or expect) in regards to coming G4-processors from Motorola? Some claim that the next portable G4 will have a 200MHz system buss, allowing DDR 400 memories to be utilized. If so, do you think that this processor will still be "strangled" like the current G4/DDR333 implementation or will it finally sport a true DDR-compatible interface?
I think it would be worth the few months of wait if I could then get an unfethered version of the G4-processor and that that would increase the long-livety of my future machine substantially. Your thoughts and advice on the matter would be greatly appreciated!
Errr, I must be misunderstanding your post somehow.
How exactly is it that the current G4 Powerbooks are not using "true" DDR? Just because they're using a slower standard of DDR-RAM doesn't mean that it is not DDR. Also worth mentioning that DDR-400 is relatively new in the industry.
Originally posted by Chagi
Errr, I must be misunderstanding your post somehow.
How exactly is it that the current G4 Powerbooks are not using "true" DDR? Just because they're using a slower standard of DDR-RAM doesn't mean that it is not DDR. Also worth mentioning that DDR-400 is relatively new in the industry.
Ummm, yes you are misunderstanding, ... maybe you should check out Apple's G4 motherboard implementation. What he's referring to is Apple's current G4 motherboard implentation using DDR. While the bus between the memory and system controller is a double pumped bus, the bus (FSB) between the system controller and CPU is a normal bus (It isn't double-pumped - it's a single 167Mhz bus). Therefore the FSB cripples or bottlenecks the CPU. Apple is using true DDR RAM, but the FSB cripples the full benefits of using DDR RAM.
IMHO, we won't see any new CPUs from Motorola, Faster G4s, maybe, but nothing with on-board DDR support.
Originally posted by crayz
Chagi - because the processor cannot actually use the DDR
What on earth do you mean with "the processor cant use the DDR" the L3 cache uses DDR, your statement does not make any sense. What would you call it if the fsb was suddenly bumped to 400Mhz without DDR?
If you mean crippeled IO then yes I'll agree that the G4 machines has got a crippeled IO system in the sense that the CPU can't use the full bandwidht provided by the memory sub-system.
And I'll agree on that the current G4's has got, by modern standards, sub par IO.
It should be mentioned thought, that the people that I know who work with Moto equipped system have been hinting for quite some time about G4's with better IO (due to info from Moto sales drones). But then again with all the spin-off rumors and the monolithical "screw up culture" that seems to reside within Motorola I wouldn't even trust them to take care of my pet cat.
So I'm taking those rumors whith a suitable truckload with salt.
2) Insofar as the 745x G4s ever getting a faster front side bus, no way, not going to happen, never. Maybe a new chip will be designed with a G4 core and Rapid-I/O and an onboard memory controller (as Amorph suspects), but you won't see a faster FSB on the 745x.
Barto
The difference between DDR RAM and SDR RAM can be read in the name: DDR = Double Data Rate (two instructions per Hz) / SDR = Single Data Rate (one instruction per Hz)
*** Please note that I am not scholared in the ways of computer hardware and what I have learned I have gotten through reading on the web. Some of the things (and names) I write above may be wrong, but the principle behind it I believe to be right. ***
Originally posted by KANE
The difference between DDR RAM and SDR RAM can be read in the name: DDR = Double Data Rate (two instructions per Hz) / SDR = Single Data Rate (one instruction per Hz)
That's correct, and also COMPLETELY irrelevent to Apple's various G4 architectures.
Originally posted by KANE
*** Please note that I am not scholared in the ways of computer hardware and what I have learned I have gotten through reading on the web.
Believe me, that's totally obvious reading your post
No CPU other than those with onboard memory controllers (eg POWERs, Athlon64s) ever sends and recieves directly to and from memory. In between the CPU and the memory is a northbridge (or system controller, or system intergrated circuit). The CPU makes requests to the northbridge for data from the memory, and the northbridge fetches the data from memory and sends it to the CPU.
It IS true that less data can be sent to the G4 alone than can be fetched from memory, but it is NOT half. System busses aren't that simple, you can't just look at the MHz and make a judgment. The G4's bus is very efficient for it's speed, and DDR is highly inefficient.
Now guess what. The Athlon is the same. The majority of Athlon computers in the world have a CPU bus slower than the memory bus. Guess what, PC user's don't call them "hacks" or "false". Do you know why? Because there's nothing wrong with asyncronous busses.
But wait, there's more.
In modern architectures, more and more devices have DMA. That's Direct Memory Access, the ability to ask for data from the memory, without going through the CPU. On the PowerBook, DMA devices include gigabit ethernet, the hard drive and most importantly the graphics chip. Using Quartz Extreme, the Radeon 9600 in the PowerBook G4 transfers buttloads of data from meory. So it's not JUST the CPU that consumes the memory bus, it's the networking, drives and graphics chip too.
Barto
A faster front side bus or an onboard DDR memory controller would vastly improve the G4's performance in many applications.
It isn't a hack BUT it is bad and the slowest of all the desktop CPUs out there.
Barto
Of course, there's nothing stopping IBM from doing the same thing, only using the G5's VMX unit and a G3 core to create basically a 7400 (the original G4). Combine that with an onboard DDR memory controller and you have a Motorola killer. That isn't as simple as it sounds but IBM thought there was a market for the G5, and they built that didn't they
Barto
Originally posted by Barto
From memory we all got whipped into a frenzy by the 7457 RM, and then Motorola cancelled it (after probably never doing any actual work on it).
I have too read somewhere that this project has indeed been canceled.
Amorph and others keep saying Motorola will probably introduce a G5 (the BookE embedded G5s, not the POWER derived 970 G5s) with a G4 core and onboard DDR controller. If that happened, I'm almost sure Apple would use it in low cost Macs.
Once upon a time there was something like 85xx series of Motorola processors. If I remember well, this was supposed to be the G5 in the PowerMacs (is this the BookE G5 you mention?). This G5-PowerMac project was also killed since, allegedly, the boxes... exploded! But what happened to 85xx since then? Is there any use of them today? Or improvements to make them usable in a notebook?
Originally posted by PB
Once upon a time there was something like 85xx series of Motorola processors. If I remember well, this was supposed to be the G5 in the PowerMacs (is this the BookE G5 you mention?). This G5-PowerMac project was also killed since, allegedly, the boxes... exploded! But what happened to 85xx since then? Is there any use of them today? Or improvements to make them usable in a notebook?
that wasn't the 85xx. the 75xx had to be the rumored G5 (back in october/november 2001) canned by motorola somewhere early 2002.
Now, there was a G4 replacement BookE chip suitable for inclusion in Macs. It was called the 7500, it was real, it was on the Motorola roadmap. Sometime late 2001 or early 2002 it got cancelled.
Then a bunch of crappy rumor web sites like MOSR and TheReg (and, ahem, Dorsal) started talking about the 85xx being the G5. Which is totally and utterly bogus, and ignores all common sense. Then when the 85xx G5 didn't materialize, they all made up bogus stories to cover their tracks, like "boxes were exploding".
Barto
Originally posted by Barto
Then a bunch of crappy rumor web sites like MOSR and TheReg (and, ahem, Dorsal) started talking about the 85xx being the G5. Which is totally and utterly bogus, and ignores all common sense. Then when the 85xx G5 didn't materialize, they all made up bogus stories to cover their tracks, like "boxes were exploding".
Barto
Originally posted by PB
It is not however clear to me if it is reasonable to expect some replacement or, at least, substantial improvement for the G4 next year (powerbooks and iMacs; I expect the iBooks will be using current G4 for a while). And what would be the candidates?
I would be surprised if the 9xx series chips are the only options for Apple next year.
That said, the G4 is probably dead. The standard G4 has stalled at 1.33GHz for a year or so. I don't see Motorola spending time on a product they consider has no future.
Looking to the future, there is nothing concrete at all. Certainly anything new will most likely be a BookE chip with a fast, Velocity Engine enabled core and onboard memory controller. An IBM BookE chip is the most likely candidate with Apple's relationship with Motorola seemingly over.
Barto
I MEAN COME ON!!!!!!!!!!