> Bruce, as an IT professional, I would have thought that you'd be aware of > 'real world' testing vs. benchmarks. I could write a benchmarking app that > runs better on Intel, hence would give better results, than PPC, or vice > versa. Benchmarking on "clock" makes no sense with a reduced instruction set.
Only Nixon could go to China, so here goes. The age of the technical supremacy of the PowerPC as a general purpose computing chip is gone. PowerPC retains important design wins in the embedded space, particularly cars, high-end service CPUs and game consoles, but the Amiga is pretty much the last stand of the PPC as a desktop platform (and yes, I have my pennies saved for an X1000 also). Intel has put big dollars into making x86 and x86_64 performant, and it shows. Although the same old disgusting ISA is slathered on top, internally the Core microarchitecture is nothing like, say, horrid designs such as NetBurst. General-purpose CPUs are their core business in a way that no PowerPC manufacturers' ever was. As was previously mentioned, Motorola was mostly interested in the embedded space, and IBM in big iron. These have very different design requirements than GP CPUs. In terms of comparison, the G5 remained competitive with, though ultimately marginally inferior to, the first generation Core machines (the G4 never was, although with large L2 cache it could get closer). When Core 2 Duo came out, all but the quad were outclassed, and now the G5 is probably half or less as performant as the current generation of i5/i7. But we expect that, because the G5 is a 2004 design. It was built to compete against Pentium 4. As far as PowerPC nowadays, the only high-performance PPCs are IBM's big iron POWER series. I personally own a POWER6, and as a workstation, it is loud and noisy and hot, just like the G5 was (because the G5 was just a POWER4 with AltiVec bolted on), but it is a great server as a dual-core 4.2GHz system and it is very very fast. It also cost me close to $10,000. That's no recipe for a home computer, and even the cooler-running POWER7 is still no easily tamed deskside tower. Consoles are built for good power for the money. Even the Wii U (POWER7 derivative, it is believed) is still in terms of CPU grunt likely to be slower than a Core CPU, but it can be made cheaply, IBM offers custom tweaks, AltiVec is a very good SIMD technology, and it's good enough. But it doesn't compare with contemporary designs either. This is all said as someone who loves PowerPC ISA. I despise x86 ISA, though mostly because I think it's ugly compared to load/store designs or my favourite CPU, the MOS 6502. But Intel, love them or hate them, has invested billions of dollars in getting the hippo to dance, and it shows. It's not something IBM, as the current standard bearer of high performance POWER, is interested in anymore. Mind you, I do think that most Power Mac software is criminally badly optimized, something I'm working on specifically for TenFourFox. G5 optimization in particular is a lost art, and important because later POWER designs share some of the same quirks. But this is still playing at the margins, and while the PA6T is a great chip, it is no match for the G5 and a 2GHz G4 will beat it. One note about Geekbench: this is actually a pretty good benchmark, not merely a clock-speed comparison. You *could* argue underoptimization for the PPC, and gcc is not a great PowerPC compiler, but Apple's gcc changes have at least made it competitive. IBM xlC is the PPC master, but it is non-standard, has a spotty track record on OS X, and a license costs about $1300. So I could see a criticism made for marginal differences, but not for the large scale differentials that you see now. Do I still think Power Macs are useful? Damn straight, which is why I'm typing this message on an iBook G4, and I use an iMac G4 and a quad G5 at home. But I don't suffer illusions about their performance. They just happen to do what I want, and they are still "fast enough." -- ------------------------------------ personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckai...@floodgap.com -- It's a big old goofy world. -- John Prine ---------------------------------- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list
