Yesterday, Apple introduced three new Power Mac G5s still based on the current PowerPC architecture. The new G5s are offered in one 2.0GHz configuration, one 2.3GHz and one 2.5GHz configuration, all of which are based on dual-core 90nm PowerPC 970MP CPUs. You can get Apple's pricing and more here but I just wanted to chime in with some of my thoughts on what's being offered:
Dual Core
All of Apple's new Power Mac G5s feature dual-core processors, but what it allows Apple to do is outfit the lower end Power Mac G5s with only a single processor and still offer the same number of concurrently executable threads as the older dual processor G5s. Granted you do lose some performance because the two cores now must share a single FSB, whereas the older dual processor machines had an independent FSB per processor. But any performance loss you'd see there is more than made up by the fact that each core now gets a full 1MB L2 cache.
The previous G5 cores were stuck with a relatively small (by today's standards) 512KB cache. It made the 90nm G5 die very small, but it also meant that performance wasn't as good as it could have been. One thing Johan found in his investigations with the G5 was that memory latency was pretty bad, and a small L2 cache does nothing to hide that.
For the two lower end G5s, the fact that the single CPUs are now dual core doesn't mean much, but the move to a 1MB L2 cache per core should result in a tangible performance increase in a lot of scenarios.
Apple does give up a bit of clock speed at the high end by moving to dual core, with the fastest G5 now topping out at 2.5GHz vs. 2.7GHz. The larger L2 cache will make up for some of that difference, but not all. Obviously the high end G5 now offers more than just a faster clock speed, it now features two dual-core CPUs. But, just like we've seen in the PC world, those applications that exhibit a high level of TLP will appreciate the dual dual-core CPU configuration, while others may actually run faster on the older dual 2.7GHz setup. For the most part, most OS X applications seem to be highly threaded in nature, and my money is on a dual dual-core configuration being the more desirable one.
DDR2-533
With the new G5s Apple has moved to DDR2-533, offering a total of 8.5GB/s of memory bandwidth. Unlike Intel's DDR2 platforms however, the G5s can actually use the added memory bandwidth. The G5 interfaces to the North Bridge via a bi-directional 64-bit FSB running at 1/2 the CPU clock speed. That means for a single 2.5GHz dual-core G5, there is about 10GB/s of bandwidth from the CPU to the North Bridge. For a dual dual-core 2.5GHz G5, that's 20GB/s of bandwidth as each CPU gets its own dedicated FSB. So in this case, there may actually be a tangible performance improvement from going to DDR2-533.
It is irritating that Apple didn't move to DDR2-667 yet, especially on their highest end configuration (and especially because it can use the bandwidth), but given Apple's relatively conservative nature whenever it comes to memory speeds it isn't a huge surprise.
PCI Express, at last
The move to dual-core is interesting, but given that the previous line of G5s were all dual processor to begin with, it's not a huge improvement. In my opinion, the biggest improvement to the new G5s is the move to PCI Express. And here's one thing I really do like about Apple, when they move to a new technology, they really move to it.
There isn't a single parallel PCI slot in the new G5s, instead you've got one x16 slot, two x4 slots and one x8 slot. The other interesting thing is that all of the PCI Express slots use a x16 connector, so although there is only one x16 slot (electrically), all four slots can fit a x16 card. Apple uses this support to their marketing advantage, by mentioning that the new G5s can support up to 8 displays through 4 dual-display PCIe graphics cards.
One thing that truly surprised me was the lack of two x16 (electrical) slots, meaning that these G5s aren't exactly configured for SLI. Given that NVIDIA is the GPU vendor of choice for Apple this time around, with the only PCIe GPU offerings coming from NVIDIA, you would think that Apple would put together a SLI-capable product with this line of G5s. There are a handful of reasons why this didn't happen and none of them really require too much thought. Apple seems to be very sensitive about preserving the usability of PCI (and now PCIe) slots, so occupying the area of virtually all four slots thanks to two large graphics cards probably wasn't at the top of their to-do list either.
Apple's new G5s get their choice of four different PCIe cards: a GeForce 6600 LE, 6600, 7800 GT and Quadro FX 4500. All of the cards support at least one dual-link DVI port, with the Quadro FX 4500 supporting two.
In the End
Apple has honestly done their best to make an attractive non-Intel Power Mac offering and obviously they had to. The dependency of OS X on high speed CPU/graphics communication means that the move to PCI Express graphics was a must, and I am pleased with the way in which Apple made that move. Offering four physical x16 slots, even if they aren't electrically x16, makes a lot of sense, and there shouldn't be any reason for PC motherboard makers to offer something similar. It may be a bit confusing, but the added flexibility is a definite benefit.
The move to dual core and DDR2 are both nice, but they will mean a lot more when we see the move to x86 next year. It is also interesting that none of Apple's performance comparisons are against x86 processors anymore :)
Dual Core
All of Apple's new Power Mac G5s feature dual-core processors, but what it allows Apple to do is outfit the lower end Power Mac G5s with only a single processor and still offer the same number of concurrently executable threads as the older dual processor G5s. Granted you do lose some performance because the two cores now must share a single FSB, whereas the older dual processor machines had an independent FSB per processor. But any performance loss you'd see there is more than made up by the fact that each core now gets a full 1MB L2 cache.
The previous G5 cores were stuck with a relatively small (by today's standards) 512KB cache. It made the 90nm G5 die very small, but it also meant that performance wasn't as good as it could have been. One thing Johan found in his investigations with the G5 was that memory latency was pretty bad, and a small L2 cache does nothing to hide that.
For the two lower end G5s, the fact that the single CPUs are now dual core doesn't mean much, but the move to a 1MB L2 cache per core should result in a tangible performance increase in a lot of scenarios.
Apple does give up a bit of clock speed at the high end by moving to dual core, with the fastest G5 now topping out at 2.5GHz vs. 2.7GHz. The larger L2 cache will make up for some of that difference, but not all. Obviously the high end G5 now offers more than just a faster clock speed, it now features two dual-core CPUs. But, just like we've seen in the PC world, those applications that exhibit a high level of TLP will appreciate the dual dual-core CPU configuration, while others may actually run faster on the older dual 2.7GHz setup. For the most part, most OS X applications seem to be highly threaded in nature, and my money is on a dual dual-core configuration being the more desirable one.
DDR2-533
With the new G5s Apple has moved to DDR2-533, offering a total of 8.5GB/s of memory bandwidth. Unlike Intel's DDR2 platforms however, the G5s can actually use the added memory bandwidth. The G5 interfaces to the North Bridge via a bi-directional 64-bit FSB running at 1/2 the CPU clock speed. That means for a single 2.5GHz dual-core G5, there is about 10GB/s of bandwidth from the CPU to the North Bridge. For a dual dual-core 2.5GHz G5, that's 20GB/s of bandwidth as each CPU gets its own dedicated FSB. So in this case, there may actually be a tangible performance improvement from going to DDR2-533.
It is irritating that Apple didn't move to DDR2-667 yet, especially on their highest end configuration (and especially because it can use the bandwidth), but given Apple's relatively conservative nature whenever it comes to memory speeds it isn't a huge surprise.
PCI Express, at last
The move to dual-core is interesting, but given that the previous line of G5s were all dual processor to begin with, it's not a huge improvement. In my opinion, the biggest improvement to the new G5s is the move to PCI Express. And here's one thing I really do like about Apple, when they move to a new technology, they really move to it.
There isn't a single parallel PCI slot in the new G5s, instead you've got one x16 slot, two x4 slots and one x8 slot. The other interesting thing is that all of the PCI Express slots use a x16 connector, so although there is only one x16 slot (electrically), all four slots can fit a x16 card. Apple uses this support to their marketing advantage, by mentioning that the new G5s can support up to 8 displays through 4 dual-display PCIe graphics cards.
One thing that truly surprised me was the lack of two x16 (electrical) slots, meaning that these G5s aren't exactly configured for SLI. Given that NVIDIA is the GPU vendor of choice for Apple this time around, with the only PCIe GPU offerings coming from NVIDIA, you would think that Apple would put together a SLI-capable product with this line of G5s. There are a handful of reasons why this didn't happen and none of them really require too much thought. Apple seems to be very sensitive about preserving the usability of PCI (and now PCIe) slots, so occupying the area of virtually all four slots thanks to two large graphics cards probably wasn't at the top of their to-do list either.
Apple's new G5s get their choice of four different PCIe cards: a GeForce 6600 LE, 6600, 7800 GT and Quadro FX 4500. All of the cards support at least one dual-link DVI port, with the Quadro FX 4500 supporting two.
In the End
Apple has honestly done their best to make an attractive non-Intel Power Mac offering and obviously they had to. The dependency of OS X on high speed CPU/graphics communication means that the move to PCI Express graphics was a must, and I am pleased with the way in which Apple made that move. Offering four physical x16 slots, even if they aren't electrically x16, makes a lot of sense, and there shouldn't be any reason for PC motherboard makers to offer something similar. It may be a bit confusing, but the added flexibility is a definite benefit.
The move to dual core and DDR2 are both nice, but they will mean a lot more when we see the move to x86 next year. It is also interesting that none of Apple's performance comparisons are against x86 processors anymore :)
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Viditor - Tuesday, October 25, 2005 - link
I agree 100%! GamePC isn't really known for their quality reviews...unfortunately, it appears that the reason AT doesn't have a review (at least this is the rumour) is that Intel haven't sent the normal review samples to anybody...quite strange for a major launch, and it tends to add legitimacy to GamePCs review.
JulesLt - Saturday, October 22, 2005 - link
AMD v Intel - I understand that the Xeon is based on their existing Pentium based designs, wheras Yonah, et al, are supposedly the work of a different design team (I'm sure someone mentioned former involvement with DEC Alpha). That's the PR anyway - we'll see. I'm sure AMD will respond, but it does look like the GHz battle is over.As for what will happen when people can compare the cost of Apple's with comparable PCs - is it really so different from the situation in the 80s when you could compare an Apple with other 68000 machines? I'd also have thought Anandtech readers would also be the first to acknowledge that a PC is more than the sum of it's components, and if you want a testament to Apple's engineering, just go look at an iPod autopsy.
They will continue to be under-powered and over-priced, because they always have been - but then it took a long time for motorists to start looking at miles per gallon rather than horse-power. It's not stopped the iPod beating cheaper more-functional players either.
Lastly - why develop software on Mac?
It's the dominant machine in several professions.
Because you can be a big fish in a smaller pond (how would OmniGroup fare in the Windows world).
Because there is more to the Mac platform than transparent windows and eye candy to keep users preferring MacOS. That's why Mac specific applications can survive against cross-platform ports, and ported open-source projects (Linux HCI typically being designed to be Windows-like). Even Microsoft understand that, by providing a native Mac version of Office - and Mac users prefer that in droves to OpenOffice and even NeoOffice/J.
Because Xcode (free with Tiger) and Cocoa make it really easy to rapidly develop a high-quality app.
It's unbelievable how much you 'get for free' with the Cocoa framework. If you don't know Objective-C you can always use Java - or Ruby or Python - which is great for developers coming from a Unix or Java background. Apple's also getting closer to the cross-platform world wheras MS seems to be looking at everything from Java to PDF to Flash and doing their own version, regardless of demand.
And because there's always room for a company doing a better alternative to Finder.
devnull - Saturday, October 22, 2005 - link
When I read for all those updates on the Mac line, one thing came to my mind... PPC provides Apple a unified platfrom from desktop to workstations and servers. Can Intel processors offer the exact same thing?Let me explain myself... If Apple wants to use the latest 970 processor it can use it in iMacs, PowerMacs and XServes. It's the same chip and most probably the same chipset (at least Northbridge). This means scale economy. When Apple goes the Intel way, in order to stay competitive, it will have to use different processors to different usage computers. A derivative of Pentium-M (nomatter how we will end up calling them) will probably power desktops such as iMacs. But a Xeon derivative will have to be used for high end workstations and servers. Xeons carry a much greater price tag and usually they are accompanied by different chipsets (both North and South Bridges). So Apple will have to buy a number of different processors, a number of different chipsets and spent more money on R&D to develop different platforms.
Another thing that troubles me is more software related... It has been suggested that Apple will prevent people from installing MacOSX to other than Mac PCs but won't stop people's attempts to install Windows or Linux on Macs. So, I'm wondering, if I had a s/w company, why on earth would I develop s/w for the Mac platform??? If I develop only for Windows/Linux I can cover almost 100% of the market, since people with Macs can always Windows or Linux on their systems and use my s/w... Why would I spent money and human resources for a Mac port???
slashbinslashbash - Monday, October 24, 2005 - link
What you aren't taking into consideration is the base price of a 970 processor vs. that of an Intel chip. I'm actually thinking that IBM is probably happy about Apple's switch from PPC to x86, and here's why: with the huge numbers of Cell CPUs in the PS3 and possibly other environments, and custom PPCs in Xbox 360's, the number of PPCs being sold in Macs each year pales in comparison. It's more of a problem for IBM to manufacture this special CPU for Apple than it's worth.On the other hand, Apple is taking whatever off-the-shelf processors Intel already has or is planning to release. I'm sure that Apple will utilize Intel chipsets as well. The economy of scale for *any* Intel processor is inherently higher than *any* PPC, unless Apple agreed to use the Cell or the X360 chip. I doubt Apple will ever use a Xeon.
What's weird about this whole thing is that I think it throws Apple's pricing strategy out of whack. One of the amazing things about the Power Mac line through the years (just taking Power Macs as an example) is how it consistently hits the same, or lower, price points with each new release. Apple has carefully managed their pricing to retain their value, and this has been possible largely due to the lack of a huge market for PPC CPU's. Look at "normal" CPU prices, which are pretty much insane (even though they supposedly are a result of scarcity). You'll pay 5 times as much for Intel's top processor as you will for the lowest processor. Same for AMD. It doesn't cost Intel 5 times as much to make a 3.8Ghz CPU as it does to make a 2.8GHz CPU, but they'll charge you for it.
I actually think that Apple has done a really good job with the pricing in the past: I have always known that if I buy a top-of-the-line $3000 machine today, then a year from now when the new models are released, it will fall somewhere in performance between the $2000 and $2500 model, and I could probably sell it on eBay for that amount. Try selling a year-old Dell or HP for over 2/3rds of its initial price! Even a homebuilt high-end computer won't hold more than half its value for a year, as newer graphics cards come out, and RAM/CPU/HD/LCD prices fall. It simply ain't gonna happen. Apple's pricing strategy has always been a way of getting buyers to think of their Macs as an investment. People who have last-gen iMacs are buying new ones for $1300 and selling their year-old ones for $1000. PowerBooks have always held their value EXTREMELY well, and again I think that this is largely due to the fact that there's not a huge, competitive market for G4 processors. There IS a huge, competitive market for Pentiums.
As for people using Windows on their Macs, I think that it will happen, but it's actually a good thing for Apple. If you buy a Mac, it *will* come with a Mac OS. You can take the time to install Windows if you want, but chances are you will at least keep MacOS around. Over time I think that many such people will gradually switch to MacOS even if they didn't plan to do so in the first place.
TheFuture - Friday, October 21, 2005 - link
Who wants to bet that this time next year "the experts" will be complaining about how slow Pro MacTels are compared to the Opteron-based computers on the market? "Why buy Apple and pay a premium when you can have Windows Vista or Linux on a FAST processor?"The latest head-to-head benchmarks between the best that Intel has to offer and the AMD Opteron show the Intel processors taking a whipping. A severe whipping! The latest sales shown that even the Windows faithful have figured out the real performance leader. This may be the first time in history where someone (Steve Jobs) has jumped from a winning horse onto a dead horse and starting beating the crap out of it while bitching about the winning horse. (The winning horse being IBM with their IC technology and processor in every high-end entertainment device on the market.)
Apple's hardware will be the same as everyone else's, only much more expensive. I give Apple two more years in the computer hardware business before they abandon ship and take on Microsoft heads-up in a software battle.
"MacTel" makes my stomach churn. What a kick in the faithful's ass by Steve Jobs.
Did I mention the Cell Processor? Which kicks every other processor on the market's ass? Steve better port MacOS X to the Cell Processor and beg IBM's forgiveness before it's too late... he better work weekends!
tallscot - Friday, November 18, 2005 - link
Re: Price.I tried to build a dual Opteron 275 and 280 PC with similar specs as the "quad" G5 Mac for less money and I couldn't do it. A "quad" G5 with RAM from Crucial comes out significantly less than a dual Opteron 280 PC using prices from price grabber.
Based on recent benchmarks of that "quad" Mac, I'd say that the speed of the two is very comparable. For whatever reason, After Effects 6.5 sees a huge speed increase on the G5, so I expect it to be faster on the Mac. Cinebench is currently screaming fast on the dual 280 Opteron with a score of 1,350 compared to the ~1,100 on the "quad" Mac. Lightwave should be faster on the Mac, though.
So this new G5 looks like a very good value compared to PCs.
mlittl3 - Friday, October 21, 2005 - link
Let's not kid ourselves. Apple has never had the performance throne when it comes to a majority of the applications out there. Even though Intel processors might be eclipsed by AMD, Apple doesn't give a rat's ass about the whole AMD vs. Intel Fanboyism thing. Intel is just a chip supplier to them. Just like Broadcom is just the chip supplier for video decoding in the 5th gen iPod.What Apple cares about is innovation. What they do with Intel processors will probably be far and above what everyone else does with their processors. Most complain about the expensive, yuppie design of most Macs but those people are just computer enthusiasts that make their own computers anyway. They hate the likes of Dell, HP, etc. as well as Apple.
TG Daily has a good article at
http://www.tgdaily.com/2005/10/21/resurgence_of_ma...">http://www.tgdaily.com/2005/10/21/resurgence_of_ma...
that talks about where the competition really lies for Apple as well as where they are going in the future. I like the point that the analyst in the article makes about the multi-computer household. People aren't going to use the same computer to control their digital home media experiences as they use to balance the checkbook or do the kids' homework. Guess which one Apple is going for.
Read the story and stop worrying about which company has the best processor performance or the best fps in every game. Apple has never been about that and never will.
TheFuture - Saturday, October 22, 2005 - link
Apple and the Macintosh has been about NOT Intel, NOT Microsoft. For those who really do think different. All that Steve Jobs has told the faithful about PPC has turned out to be a big lie. Why believe him now?As for innovation, Apple didn't invent USB, Ethernet, SATA, PCI Express, Wi-Fi, Bluetooth, DDR2 SDRAM or ANY of the technologies that will be in their MacTel hardware. Their one innovation, FireWire, will eventually give way to USB or even UWB wireless for multimedia. Onto the trash heap with their contribution to the PPC ISA.
If Apple's computers use Intel processors, Intel chip-sets, and industry standard interfaces, memory and media, then what does Apple really bring to the table other than MacOS X? Are people really willing to pay an extra $500 or more for an Apple logo and access to MacOS X?
Apple's Intel hardware will have NO distinguishing features at the end of the day. At least with a different processor ISA, the faithful could rationalize their expensive Apple hardware. Now this rationalization is not only gone, they have to submit to the indignity of being an Intel lemming.
The ONLY advantage I see in moving to Intel will be to allow Windows Vista to run side-by-side with MacOS X for business and engineering application support. To eliminate the argument that Apple hardware can't run critical applications. I suspect this may backfire on Apple, exposing Mac users to Vista which may turn out to be "just as good" as MacOS X and able to run a much broader range of software - on the same ole Intel processor. Mac users may just boot into Vista one day and never go back...
michael2k - Saturday, October 22, 2005 - link
Apple would not complain if everyone bought Macs to boot Vista.Likewise neither would Microsoft.
jkresh - Thursday, October 20, 2005 - link
Will Apple be willing to step down when going x86 (ie go from 2 dual core g5's to a single dual core intel?) or are they expecting dual processor intel systems or one 4 core (which I didnt think would be available on the home side that fast?)