Freescale reveals details about dual core G4 e600

I earlier posted an article describing the new dual core G4 class e600 chip from Freescale. Freescale has now added some details in a press release. Some of the details are listed below:

e600 MPC8641D Dual Core (Pin-compatible single core version also available)
1.5+ GHz
Two 1 MB L2 caches
Dual AltiVec units
15-25 Watts typical
Integrated memory bus, up to 667 MHz
1 Gbps Ethernet
90 nm

This MPC8641D brings the possibility of a dual core PowerBook with reasonable power characteristics, although one wonders if Apple will choose to use a single core chip, either a G5 970FX derivative or else a single core variant of the MPC8641D.

In addition, Freescale will release the G4 MPC7448, which is pin-for-pin compatible with the MPC7447A, but which includes double the L2 cache. The MPC7448 is also based off the e600 core, but does not include an integrated memory controller.

The MPC7448 would be the logical chip upgrade for the iBook. It's also possible that Apple would use this chip in the next iteration of the PowerBook before it goes to a new architecture.

COLSA Xserve G5 supercluster completed

Several new supercomputers have been announced this year built using Apple G5 Xserve, and one of the largest, built by COLSA Corporation, has recently been completed.

Called MACH5, it incorporates 1566 dual processor G5 Xserves for a total of 3132 processors, over 40% larger than VT's supercluster which reached third place in the world last year.

COLSA states it assessed several different architectures, but ultimately chose the Apple Xserve G5 system not only because of its low cost and high performance, but also because of its comparatively low power requirements.

It will be interesting to see where COLSA's MACH5 places in the next Top 500 list of supercomputers (assuming COLSA submits Linpack performance benchmarks to the list). VT's System X is virtually assured a place in the top ten, but MACH5 uses a slower type of interconnect than System X does and thus will likely have lower Linpack performance, despite its higher number of processors.

iMac G5 Developer Note available

Apple has now published the Developer Note for the new G5 iMac.

There are a few interesting things in the note that weren't known previously:

1) The iMac G5 supports dual-channel memory:

Additional DIMMs can be installed. The combined memory of all of the DIMMs installed is configured as a contiguous array of memory. The throughput of the 400 MHz memory bus is dependent on the DIMMs installed. If only one DIMM is installed, the memory bus is 64-bit. If two non-identical DIMMs are installed, there are two 64–bit memory buses. If two identical DIMMs are installed, the memory bus is 128-bit. Identical DIMM pairs have the same size and composition and provide the fastest and most efficient throughput.

This means that if you install two identical DIMMS, you get twice the theoretical throughput. It also means the system bus speed may become the bottleneck.

2) The iMac G5 may support DDR333:

The RAM expansion slots accept 184-pin DDR SDRAM DIMMs that are 2.5 volt, unbuffered, 8-byte, nonparity, and DDR400-compliant (PC3200). The iMac G5 only supports DIMMs up to 1.25” in height...

DDR266 (PC2200) or slower DIMMs do not work in the iMac G5 computer.

If the iMac G5 does support DDR333, then it would support dual-channel DDR333. Theoretically, in this configuration memory bandwidth would still be faster than system bus bandwidth, at least in ideal conditions. Theory aside, support for dual-channel DDR333 would make DDR333 memory in an iMac G5 a reasonable compromise for those on a budget and who already have DDR333 memory.

3) The iMac G5 uses a 90 nm system controller:

The processor bus is an up to 600 MHz bus connecting the processor to the U3L IC. The bus has 32-bit wide data running in both directions. The processor has 42-bit wide addresses.

The iMac G5 system controller is built with 90-nanometer SOI technology.

One wonders if this was one reason for the new iMac's delay.

Steve Jobs back at work

c|net reports that Steve Jobs is already back at Apple, albeit part time for now. He should be back full-time by the end of September.

It sounds like his pancreatic neuroendocrine tumour was indeed low risk. That's great if true.

We wish him well.

iMac G5 best seller at Apple Store

Even though the iMac G5 is not even shipping yet, it is now the number one best seller at the Apple Store, beating out even the iPod and iPod mini. In fact, no other computer is on Apple's top ten list.



This is very good news for Apple. One can only hope that the sales continue to be good in a few months, after the initial pent up demand is satisfied. I suspect that in the revision B G5 iMac, Apple will update the CPU, and more importantly the GPU, to try to ensure continued strong sales.

Freescale to unveil new G4 MPC7448 in September

Freescale will be unveiling the details about its new G4 MPC7448 CPU at SNDF 2004 Europe at the end of this month. This chip is the evolution of Freescale's tried-and-true G4 744x line. It appears to be a lower power version, possibly due to a die shrink.

Note that this chip announcement is in addition to the planned October announcement of Freescale's next-generation chip line, the e600. Unlike the G4 744x, the e600 will offer support for dual cores and an integrated memory controller.

While not as advanced as the e600, the G4 MPC7448 will still likely be very important to Apple. Apple has already stated that there will be no G5 PowerBook in 2004 and it is possible that Apple will release another G4 PowerBook this year based off the MPC7448. This chip will likely have a much faster time to market than the e600, and will have low power requirements perfect for a new Apple laptop update.