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Apple To Discuss HyperTransport For Future Macs
macrealist writes "CNET is reporting that Apple will discuss the use of HyperTransport in Macs at the Developer's conference. The interesting thing is that the article claims that Apple is not likely to use hypertransport to link the CPU to the memory, but instead to link chipsets together because IBM would have to 'to adapt it to the Power architecture.' But according to arstechnica, the 970 does have a frontside bus that operates at similar speeds to Hypertransport."
<pedantically> I think that Apple has already developed a tried and true solution for external, non-ethernet-based, high-speed data transfer. It is called FireWire800.
Of course, an IP substack can be built on top of the FW, to have additional networking options. (Check out)</pedantically>
0.02â
Apple is a member of the HyperTransport Consortium. They have a hand in the development of the technology.
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The internet is the greatest source of biased information in the history of mankind.
First of all: A "frontside bus that operates at similar speeds to Hypertransport" most likely isn't Hypertransport - just like a car with performance similar to a Porsche isn't a Porsche. So you can't just hook up a 970 (or POWER/PowerPC) to a Hypertransport link.
Furthermore, linking a CPU to main memory via Hypertransport (a point-to-point link) means you can't share the memory with other CPUs (unless you have dual-ported RAM - uhh, yeah, good luck with that plan).
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
The next time you play around with a Mac OS X machine look inside an application bundle. See those nib files? They provide the user interface and you can modify them using apple's developer package tools.
Yes, the entire computer is skinnable, user apps included. Now this doesn't include classic apps (which you won't be using much of), unix apps (which don't use NIBS) and monolithic code not in a bundle (like RealBasic). For the rest of the 90% of Mac apps, you can really mod to your heart's delight. Most people don't do this because they *like* the way Apple makes everything work with everything else. But if that's what floats your boat...
To do it right, you'd have to get a new bus as the chips are being strangled by bandwidth bottlenecks on current bus designs.
I don't know where these rumors get started.
The combination of fat caches, low latency, and predictive fetching basically negates the memory bus bottleneck in the current-generation (MaxBus-based) Power Macs. Even in SIMD instances, the processor generally doesn't have to wait on data that much. (This is especially true in SIMD instances, because these are almost always sequential-read applications, which makes those fat caches and predictive fetching work up a sweat.) Consider Apple's AltiVec-optimized BLAST, for instance. It's 10X faster than BLAST on a Pentium 4. It's not memory-bound. It's compute-bound.
What's that famous Seymour Cray quote? "A supercomputer is a device for turning compute-bound tasks into I/O-bound tasks."
So if anybody produces PowerPC 970 upgrades with MaxBus interfaces, they're almost certain to be good buys. Unless they cost thousands of dollars, of course. A dual-1.8 GHz (pulled that number out of my ass, guys) Power Mac G5 (pulled that out of my ass, too) will be faster than a dual-1.8 GHz upgrade in a MaxBus G4, but it'll still be considerably faster than the G4 was originally.
It is looking more and more like the IBM-970 does use/support Hypertransport.
"Six GDA IP cores are available through IBM Blue Logic IP Collaboration Program including HyperTransport Cave, Tunnel, Host and Bridge, 10 Gigabit Ethernet MAC, and SPI4.2 link controller. Information on these IP cores is available on IBM and GDA web sites."
The above is from this news release from the Hypertransport Consortium http://www.hypertransport.org/pr_050503b.htm
Shadow
For example, if I don't buy a SuperDrive-equipped box now, can I add one later?
:). It runs virtual PC quite well (emulates a 667 MhZ P III), only concern is RAM (i have only 256 which is really not enough when switching back and forth OS X and Windows XP). 1 GB RAM should do. RAM is dirt cheap these days.
Yes: internal or external. Careful about support though: go to Apple's search page and look for DVD-RW. These are supported officially, others are not.
Are there any other things like this I need to be careful for that are "missing" from lower models?
The bottom of the PowerMac line is missing, well, nothing. All PowerMacs have an AGP 4X slot, plus 3 (or four?) PCI slots, so you basically can add what you want.
Connectivity: an airport extreme slot, bluetooth-ready, FireWire 800, USB 2 (the OS doesn't support it yet, but apparently there are some hacks that work), Gigabit ethernet. You can add Fiber Channel (2 Gb/sec) too.
Expandability: you can add 3 more hard disks (RAID support - I think), a second optical drive, go up to 2 GB RAM (maybe 4 GB with 1 GB sticks?). Some vendors sell G4 upgrades (some currently manage to get their Cube at 1,42 GhZ), but at a price.
You can change the video card; all Powermacs come with either Radeon 9000 (dual display, one ADC, one VGA/DVI, adaptor included), 9700, or GeForce 4 Titanium.
What is good about Powermacs (in my opinion) is not that you can upgrade like you would on any PC, but that even without upgrading, well, it still works after 15 years (I have relatives that type text on a Mac Classic / Apple printer). When I replace my G4 (in 3/4 years), it still will do a very sweet SSH / web / email server (maybe Darwin or Linux)
What are the architectural differences between the iMac/PowerMac and iBook/PowerBook?
iMac still has no DDR (!), its SDRAM. You can upgrade to 1 GB. It comes with a SOLDERED video card (GeForce 4 MX). Don't ever think of upgrading anything on an iMac (except RAM and hard disk). You can have airport or airport extreme (depending on the models). But my 3-year old iMac (g3 400 MhZ) runs Mac OS X fine, does Word, internet and email jobs for my dad.
iBook is still G3, maxes out at 640 MB of RAM. I consider it to be a cheap laptop, made for students (well, it manages to do serious DV video editing, so I presume it's powerful enough).
I never really used a powerbook, but they look like sweet machines. DDR, Radeon Mobility 9000, VGA and SVideo out.
As for speed: I have a dual 1 GhZ, it's fast enough. I don't know about your business-type apps (if this means word-processor, well, any mac is enough; if it means Oracle database, well, I just don't know
Quartz Extreme: it's not about the processor (only iBook still has G3 anyways.), but about the graphic cards: you need more than 16 MB VRAM to enable Quartz Extreme (so all the current line, including iBooks, support it).
Anyway: WWDC is REALLY close now, you should wait for the event and decide wether you can wait for the 64 bit processors and huge FSB, or pick up the discounted G4's Apple is sure to sell right before introducing the 970's to the market.
Here, hope it helped. Applestore / Knowledge base webpages should help, or you could check www.xlr8yourmac.com
Hello! I'm a disaster waiting to happen!