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View Full Version : New Powerbooks' Processor: overclocked, or PPC 7455?


BigDawgES
Apr 19, 2004, 11:11 AM
The following article questions whether Apple will stick their more advanced G4 chip (PPC 7455) into the latest PowerBooks revision or simply overclock their older PPC 7447.

http://www.insanely-great.com/news.php?id=3317

I'd be grateful if anyone can find out which one apple chose to use in today's PM revision.

Bear
Apr 19, 2004, 11:22 AM
The following article questions whether Apple will stick their more advanced G4 chip (PPC 7455) into the latest PowerBooks revision or simply overclock their older PPC 7447.

http://www.insanely-great.com/news.php?id=3317

I'd be grateful if anyone can find out which one apple chose to use in today's PM revision.How about the 7447A?

And it's not overclocked.

And in the article you posted the link for? The Ti 800MHz Probably beat the 12" 867MHz due to a faster system bus, not due to the difference in cache.

Apple has never sold a system with an overclocked processor.

Mr. Anderson
Apr 19, 2004, 11:23 AM
How about the 7447A?

And it's not overclocked.

where did you find that?

D

Bear
Apr 19, 2004, 11:37 AM
where did you find that?

DI found it here (http://e-www.motorola.com/webapp/sps/site/prod_summary.jsp?code=MPC7447A&nodeId=018rH3bTdG8653) - excerpt:The MPC7447A processor is a high-performance, low-power, 32-bit implementation of the PowerPC™ RISC architecture. Key architectural features include 512 KB of on-chip L2 cache, a 64-bit bus interface and a full 128-bit implementation of Motorola's AltiVec™ technology. MPC7447A processors are ideal for leading-edge computing, embedded network control and signal processing applications.

Designed as pin-compatible replacements for Motorola's MPC7447 products, these new processors have been shown to reach speeds of 1.5 GHz. MPC7447A processors benefit from Motorola's silicon-on-insulator (SOI) process technology, engineered to help deliver significant power savings without sacrificing speed. Low-power versions of the MPC7447A are available.

CrackedButter
Apr 19, 2004, 11:39 AM
How about the 7447A?

And it's not overclocked.

And in the article you posted the link for? The Ti 800MHz Probably beat the 12" 867MHz due to a faster system bus, not due to the difference in cache.

Apple has never sold a system with an overclocked processor.

cough *powermac G4 1.42's* cough cough

But they do sell mac with UNDER clocked processors ;)

Bear
Apr 19, 2004, 11:41 AM
cough *powermac G4 1.42's* cough cough

But they do sell mac with UNDER clocked processors ;)They were not overclocked. The chips were rated for 1.42GHz by Motorola.

As for underclocked... actually there is usually a range of speeds a given processor can run at. So they wouldn't be underclocked either. They would just be clocked at a slower certified speed. [The range of speeds only applies to some processor models from some chip manufacturers.]

brhmac
Apr 19, 2004, 12:29 PM
As for underclocked... actually there is usually a range of speeds a given processor can run at. So they wouldn't be underclocked either. They would just be clocked at a slower certified speed. [The range of speeds only applies to some processor models from some chip manufacturers.]

So there!

Always a pedantic person in every crowd.

Sun Baked
Apr 19, 2004, 02:26 PM
The 7445/55 is a LARGER process version of the 7447/57.

At least the most recent version of the 7455 (there were quite a few as Motorola baby stepped to the 7457s).

The smaller process allowed them to add a bigger cache within the same space, and you'd probably say the 7457s are the more advanced chips right now (and they do support the L3 cache, in fact they support more than the 7455.)

Now Apple didn't include the 7457 in the current crop and elected to go with the 7447 (one without the L3 cache) because the 7447 was as fast as the 7455 with L3 cache -- and putting fast L3 cache with the 7457 would be more expensive.

Plus there might have been issues with the 7457s L3 cache. :rolleyes:

---

Anyways the 7447s have (512K SRAM on-chip L2 cache) and are supposed to be less expensive than the 7445s and probably quite a bit less than a 7455 with a lot of L3 cache.

So it would be a little strange to choose a hotter, bigger, more expensive solution (7455 with L3 cache) than one as fast or faster that's smaller, cooler, and less expensive.

aswitcher
Apr 19, 2004, 02:52 PM
Anyways the 7447s have (512K SRAM on-chip L2 cache) and are supposed to be less expensive than the 7445s and probably quite a bit less than a 7455 with a lot of L3 cache.




I hope its this newer chip 7447 with better power management.

Sun Baked
Apr 19, 2004, 03:03 PM
I hope its this newer chip 7447 with better power management.Looking at the MC7447A Rev 1.1/1.1.1 Qualification Report (pdf) (http://e-www.motorola.com/files/32bit/doc/rel_qual_info/MC7447ARQI.pdf) I'd almost be able to say, "Yes they are 7447As."

Since the spec for the 1.33 and 1.5GHz chips are usually the ones Apple's used in the portables in the past -- the W spec series.

But I also haven't seen a part number for laptops since they swith from the XC74... to the newer part numbering scheme MC74...

Dont Hurt Me
Apr 20, 2004, 01:37 PM
No more L3? interesting isnt it, Owc Merc Extreme is a 7457 with 2 mb of L3 and i have been pretty happy with this thing. almost a year old. throwing that in the quicksilver was a good move. still thought we would have seen more advancement but moto got it going faster then the 1.42(ahem overclocked G4 hence wind tunnel, massive sinks yada yada yada.) way to go moto took more then a year to squeeze-ever so slowly -.60 mhz?? and the G5 ?will it be a year before rev B?? man Apple is taking such a long time to update stuff and then when its updated they remove all L3 from G4. The CPU situation at Apple is kind of rotting. no progress at all on the CPU front.

yamabushi
Apr 21, 2004, 06:57 AM
I think that the new Powerbooks probably do use the 7447A. These are not in the same league as the 970 and 970fx but it is good to see an updated moto proc anyways.

The CPU situation at Apple is kind of rotting. no progress at all on the CPU front.

Well the G4 clock speed improvements have shown progress. A couple of years late but better late than never. The recent bumps are really pretty good in my opinion.

Here is a summary of the increase in clock speed from previous top end verions of various models: eMac +25%, 12"PB +33%, 15"PB +20%, 17"PB +13%.

I find the fact that less expensive models had a larger percentage improvement to be a very positive sign. I would like to think that this could mean the beginning of a trend towards less crippling of the low end.

The Cheat
Apr 21, 2004, 11:33 PM
When will people understand that Apple has no need to "overclock" its chips. "Overclocking" implies that one is over-riding the set factory clock multiplier or FSB. Since Apple can set these themselves, they have no need to overclock. A chip is as fast as it can be run without becoming unstable.

ZildjianKX
Apr 22, 2004, 01:31 AM
When will people understand that Apple has no need to "overclock" its chips. "Overclocking" implies that one is over-riding the set factory clock multiplier or FSB. Since Apple can set these themselves, they have no need to overclock. A chip is as fast as it can be run without becoming unstable.

Well, the term is used rather loosly here, implying that Apple is selling the same chip rated for the same clock speeds, but simply charging more for the same thing running at a different effective clock speed.

The Cheat
Apr 22, 2004, 01:46 AM
Well, the term is used rather loosly here, implying that Apple is selling the same chip rated for the same clock speeds, but simply charging more for the same thing running at a different effective clock speed.

Well, the same is done by any CPU manufacturer. That is why it is possible to take a P4 2.4C chip and have it run stable at 3.4+GHz.