notes on new power mac (was Re: clusters v SMP)

[Mark Hahn]

> The 4GB memory restriction of an Intel node would be too 
> restrictive for some of our users. The majority I suspect are 

reading this triggered me to look at the specs of the new Mac.
after all, the PPC is a reasonably nice architecture, and afaik
isn't maimed by 32b-isms.

anyway, ignoring Apple's inane marketing-twit-speak, the specs are:
	dual PPC G4/1000
	256K onchip L2
	2M per-CPU DDR sdram L3 cache
	133 MHz FSB, 
	3 slots of PC133 (non-ddr) sdram
	4 64x33 PCI slots,
	builtin 1000bT
	360W max power.

personally, 2M seems strangely small for DDR, since it's not 
either fast or wide.  probably a single chip.  they'd obviously
be much better off (at least from a beowulf perspective) by 
biting the bullet and finally engineering a decent dram bus.
3 dimms also means it has no ram-size advantage over commodity 
(ia32) parts.  builting gigE is interesting.

in short, a nice workstation, but not well-suited to cluster nodes.