G5 discussion


IBM 90nm G5 chip to 'outrun' Prescott, Athlon 64

By Tony Smith

Posted: 12/02/2004 at 16:02 GMT

IBM's technically as yet unannounced PowerPC 970FX has won the
Microprocessor Report Analysts' Choice Award for Best Desktop

And according to MR editor-in-chief Peter Glaskowsky, Intel and AMD
had better watch out.

The 970FX is the 90nm die-shrink of the original 130nm PowerPC 970,
launched back in October 2002 and finally shipped last summer, most
notably inside Apple's Power Mac G5.

IBM is expected to launch the 970FX formally next week at the IEEE
Solid-State Circuits Conference (ISSCC), along with its PowerTune
technology, which adds SpeedStep-style clock frequency scaling that
can synchronise across multiple processors.

The chip should be shipping very shortly. Apple's Xserve G5, which is
based on the 970FX, is due to ship this month.

IBM documentation has already revealed the 970FX's impressive power
characteristics: 24.5W at 2GHz. The 130nm 970, by contrast, eats up
51W at 1.8GHz.

That will help 970FX-based machines scale very well against Intel's
90nm offering, Prescott. "The 970FX should yield well at 2.5GHz, up
from the 2GHz speed of the 970 used in Apple's Power Mac G5," writes
Glaskowsky. "This 25 per cent increase in clock rate will not soon be
matched by Intel or AMD. Prescott is struggling to eke out minor
clock-rate improvements, and AMD will need to wait for its own 90nm
products - due in H2 - to achieve substantial speedups for Athlon 64.

Glaskowsky also believes Apple will be able to get the part up to 3GHz
by the summer - a promise made by CEO Steve Jobs last year. "That's
an aggressive target," Glaskowsky notes, "but it should be achievable.
The 970FX has the necessary architectural sophistication in its deep
pipelines to make this speed possible, and IBM has the necessary
technology in its CMOS 10S process.

"At 3GHz, the 970FX should outrun the chips we expect from AMD and
Intel in the same time frame."

But the story doesn't just centre on clock speed. Because the 970FX is
a die-shrink, it should come in at just over half the size of the
118mm², says Glaskowsky. The upshot is that IBM should be able to
punch rather more 970FXs out of a 300mm wafer than Intel can
produce 112mm² Prescotts. AMD is still on 200mm wafers and will be
until 2006.

That yields IBM "a large cost advantage" over Intel Prescott, says
Glaskowsky, which bodes well for Apple's ability to balance margins
against system cost going forward.

IBM's edge in cpu/power ratio does not surpise me. Intel's enormous power usage is why a company like Clearspeed exists. Clearspeed makes math co-processors that, if you program your code correctly, can increase your CPU/power ratio dramatically.

I wonder though, how much CPU/power really matters to buyers. Education purchasers tend to pawn off power costs onto the university. Business divisions tend to pawn them off to "overhead". It's only when you look at things more globally that power consumption makes a difference. Plus, infrastructure costs are only around 10% of total costs anyway - as opposed to people costs which can be 50-60%.

As for the clock speeds or costs, I'll wait until the benchmarks come out, or until I get a quotation.

Looks very interesting. We can always welcome new competition as it will drop prices for us consumers. I'm sick of having a one trick pony like intel for the longest time.

cajones, there are a few Linux and BSD that support PPC.

Yellow Dog works on Apple's G5 already. But the thought of
bastardizing Apple's hardware is sacriligious. ;-)

I'm sure it will work with your Mercury hardware. You may also
consider Gentoo for PPC. Its currently available for G3/G4. The G5
version is expected soon. I've always been a big fan of Gentoo since its
portage is similar to FreeBSD's ports tree.

You guys are aware that AMD hijacked the dudes responsible for the alpha which consistently crushed all other risc processors?

They split to amd when DEC was sold to compaq.

Compaq got the shaft big time.

Expect to see more risc like processors from both AMD and intel.

Remember that it takes more throughput for a RISC processor to do what a CISC processor can.

Cajones, how do your customers feel about running Gentoo or Yellowdog? From my perspective, Gentoo has a hobbyist reputation, and Yellowdog does not have the name of RH or Suse.

If I were your customer, I might prefer to port my software and run G5 as it was meant to be run - with OSX. Or else take the performance hit with Xeon. I guess it would depend on my app, and porting difficulty.

there's also Debian for the PPC.... IIRC...

if someone is anal about using Gentoo, you could always use Debian.

Debian has a more formal rep than Gentoo generally, even though they are both community based.

Debian has a more formal reputation than Gentoo, but still has a hobbyist reputation. Last I checked, Debian has about a 20% overall Linux usage, but almost none of the business world. There are three problems with Debian (IMO). The first is that it is really old. The second is 3rd party vendor support. Some 3rd party vendors require RPM. FOr instance the Intel math libraries are packaged in RPM's that are packaged WITHIN executables - so you can't use alien. Many 3rd party vendors will only support their product on RH (or sometimes Suse). THe third is that the kickstart equivalent (jumpstart on Solaris) is not quite as nice. This is important when you scale to 100's of machines.

At Linuxworld, even with RH's new pricing, I did not see anybody migrating to Debian (or Gentoo).

But, the importance of these issues varies between clients and companies. So yellowdog, debian, or Gentoo may be just fine for Cajones's clients.