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Do I want a 6500

Nifty950

Well-known member
I am considering a PowerPC 6400 / 6500 over a 68k IIsi, as these still run system 7 and 68k apps but are much quicker machines. anything I should know / is there any reason to not get one or maybe should i consider a 7200 - 7600 series?
 

joshc

Well-known member
I'd still shout for a 650 over any of those models, although I've just checked eBay US and there aren't any for sale at the moment. You might want to create a WTB post in our trading post to see if somebody on this forum wants to sell one to you.

7200-7600 have PSU issues and are just generally weird machines, I hate the Outrigger case they used on those as well. But some people love these machines. They are PCI too, so no possibility to use NuBus cards in them.

68k code runs slower on a lot of PPC Macs vs a fast 68040, but SpeedDoubler 8 helps with this.

Brittle plastics affect all of the models you mentioned, but not the 650 - that's a thick plastic front/back with the main case manufactured from metal. I wouldn't be surprised if any of the models you mentioned get damaged in shipping.

The other way of looking at this: Get something, anything and then go from there. Buy a 6400 / 6500 if you found a cheap enough one, see if you like it. If you don't, sell it on and then try something else. These Macs just don't come up as often as they used to now (most were thrown away when they were still considered ewaste and now we're left with a small supply of them remaining).

Edit: Forgot to mention the cool thing about the 6400/6500, they have a built-in subwoofer which makes the Performa boot chime very loud.

Good luck.
 

jeremywork

Well-known member
Whether you want one is your call, but I can outline some differences between them.

The 6400 is based on Alchemy architecture, and is essentially the same machine as 6360 (6300/160) and 5400, but in minitower form. They run a 40MHz bus, various 603e speeds, and can accept a 256k cache module which came installed from the factory in some configurations. Aftermarket caches up to 1MB exist, but are more rare than the G3 accelerators which can also occupy this slot. These feature 8MB or 16MB of soldered memory, can accept 128MB additionally, and include 1MB of VRAM used a fast framebuffer setup similar to Quadras.

The 6500 is based on the Gazelle architecture, shared by the 5500 and Twentieth Anniversary Macintosh (TAM.) These run a 50MHz bus, various 603ev CPUs, and included 256k caches as standard, and 512k caches on 275 and 300MHz models. They can also accept the G3 upgrades and aftermarket cache modules. These do not feature any soldered memory, and therefore have a slightly lower memory ceiling of 128MB total (I’ve heard soldering some on could be an option.) They include 2MB of VRAM, utilized by an onboard ATI 3D Rage II, which isn’t the fanciest thing with only 2MB but nicer than the simple framebuffer. Due to a factory oversight, Gazelle machines do not detect any PCI devices behind bridge chips, which can only be worked around by manually specifying the undetectable sub-devices in nvram. A few USB/FireWire cards have been patched this way to work, but it should be noted the PCI is much less flexible on Gazelles than Alchemy models. Simpler one-function PCI devices usually work fine.

For both architectures there is mostly feature parity between each set of three models, though minitowers have an extra bay for zip drives (or secondary 5MB/s SCSI hard drives.) As @joshc mentioned, the minitowers came with an internal subwoofer (well, actually a full range speaker- the low-pass filter is enabled only when something is plugged into the audio out minijack.) The TAM also includes a subwoofer, which is separated and houses the power supply. The AIO models (obviously) have screens built in, while the 6360, 6400, and 6500 require external monitors. All models have slots for optional composite/s-video in boards, and TV or TV/FM combo tuners (require populating video-in board.) TAMs include both (including FM) from factory. All have front panel headphone jacks, volume buttons, and IR receivers for use with a remote control. The minitower models feature two PCI slots and a Comm Slot II for modem or ethernet; the AIOs only one PCI slot and Comm Slot II. The TAM requires a larger “fat back” rear panel and individual risers for its PCI and CSII slots, which were included from factory but often become separated from the machines over time. All models feature a GIMO connector for internal AV loopback from the 7” PC Compatibility card, or can be used for an external video port which mirrors the main display (DA-15 or composite+s-video)

Collectively, these six models, the 4400 and clones that share its Tanzania architecture (Tanzania II to reach Gazelle-parity,) and PowerBook 2400/3400 are all known as PowerStar machines (second generation PowerPC, PCI-based LC series.)

I can’t give nearly as detailed a rundown on the 7200-7600, though I will echo the comments about fragility of the outrigger cases. The Power Mac G3 desktops in this form factor seem a bit more robust despite having the same design. Most are 601, 604, G3, and G4 capable however. The 7600 is similar to the 7500 but with faster CPU modules installed. The 7300 is like the older 75/600 but with no AV subsystem. These three share the TNT architecture.

7200 is the odd one out, as it uses the same Catalyst architecture board Apple offered to be used in clones. The 601 is soldered, only four RAM slots instead of eight (but more common 3.3v FPM!) and a GIMO internal video loopback port is installed for PC Compatibility cards (no three-ended adapter necessary.) G3 accelerators do exist but sit in the PCI slot, and these are beloved by Amiga enthusiasts and command even crazier prices than the TAM owners place on the L2 cache-based accelerators. No AV subsystem is present.

These four, the clones that share architecture with the 7200, the 8500, 8600, 9500, and 9600 are collectively called PowerSurge machines (second generation PowerPC, PCI-based workstation series)
They all can utilize 128MB per DIMM slot, totaling 512MB, 1GB, or 1.5GB maximum. All feature a simple fast framebuffer setup with expandable VRAM, up to 4MB (except the 9500 and 9600, which have no video subsystem at all.) 10Base-T was onboard all models, and all but 7200/clones featured a secondary 10MB/s internal-only SCSI bus for hard drives (PowerStar used IDE.)

Tangentially, the PowerMac G3 models would be the successor to PowerStar. PowerSurge was to be replaced by PowerExpress, which was cancelled before release (the G3 was fast enough to outperform it, and Apple was nearly out of cash.) To dramatically oversimplify: G3 was a reworked 603 with backside cache; G4 was the 604 updated similarly and equipped with 128-bit vector scaling (altivec) support. Someone else will hopefully point out which pieces I got wrong here :)
 
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