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Dual G4 Mac Cube
ijx writes: "Those of you with a hardware-hacking bent should enjoy this - a Mac Cube modded to accomodate dual processors, courtesy of AccelerateYourMac. It seems that it uses the same dual-proc module as a Sawtooth G4 Tower. My question: will it melt?"
This is a by-product of the PPC architecture used by Apple. You're thinking in a PC mindframe, where the CPU sockets are built directly onto the motherboard, and to do a dual setup you need a mobo that supports two CPUs. A Macintosh is different. The CPU is on a separate card. The dual CPU card is the same as a single CPU card, but with two CPUs on it. It connects to the motherboard in exactly the same way. Now, I've never taken a mac apart or done a CPU upgrade, so I don't have much authority here, but that is the gist of how it's done. PC architecture vs. Mac architecture.
The G4/450's that are in this Cube only use 7-11 watts each. Compare to 50-70 watt Athlons and Pentiums, and you can get an idea of why this works without a fan. Standard Cubes run cool, so there was some room there. He plainly states that he is monitoring the CPU temperature with a utility app and it's cool enough. It may not work in Florida if you don't have air conditioning, but that's why he checked with the CPU temperature utility.
The G4 towers have a fan, but they are there at least partially because the box has room for three more hard drives, one more removable drive, and four PCI cards in addition to the stock stuff, so you have to leave a big margin for error. The fan switches off when the machine sleeps, though, and the boxes don't run hot. Also, the power supply is inside a G4 tower, but it is outside on the Cube.
Apple stopped using ZIF a few years ago.
In the tower machines, pre-cube, it went like this:
G3 Yosemite - zif G3 processor, Blue and White minitower.
G4 Yikes! - Zif G4 processor, Graphite and clear, PCI graphics.
G4 Sawtooth - no zif, Apple used a large D shaped white connector and used screws to stabilise the board that carries the processor. AGP graphics.
G4 Mystic - same processor interface as Sawtooth, first of the DP series, with 450DP and 500DP. Also known as Gigabit ethernet.
G4 V'Ger - 466, 533DP, 667, 733. Same as gigabit ethernet, with 133mhz system bus.
G4 - Quicksilver - 733, 800DP, 867. Same as gigabit ethernet model with 133mhz system bus.
G4's from Mystic or newer won't work on Yikes!.
G4's from V-Ger and newer won't work on Mystic (133mhz bus versus the 100mhz bus...other differences..)
XLr8.com sells a dual G4 upgrade card, but it only works on Yikes! and Yosemite (ZIF).
I wish I had better details on where the modifier of the Cube got the extra processor card from a Mystic, and how he added the extra pad to match the dual processors. Was it just held in place with thermal goo and pressure from the retention of the heatsink?
--I don't understand why this comment got modded up. RISC vs. CISC has nothing to do with how much power a device uses. RISC arcs have a wide range of power consumption characteristics, from your low-power ARM to your space heaters like the Alpha.
As I recall any of the Alpha line of microprocessors (a pure RISC design) uses significantly more power than any of your desktop x86 processors (I believe in the 100W or more range).
I imagine the reason the conclusion is incorrectly drawn is due to the fact that x86 is one of the only (if not the only) high performance CISC architectures out there. Since he has only one sample point, the poster must have assumed that "all CISC designs consume more power than RISC designs".