Originally Posted by zeph
I know. It got a little muddled with the post above, but I actually posted this on the previous page. BTW, thanks to its superior architecture the MacPro is only marginally slower in the Geekbench. Its CPU is quite a bit slower than the i7.
I have it on good authority that the i7's and Xeons are essentially the same, other than the latter's multi-processor support. That is obviously not an issue with single-CPU MacPros, hence my plea for a cheaper base-model with an i7, rather than the Xeon.
OK. I didn't want to go there. But if you insist...
1- The Xeon W3xxx don't
support multi-processor, they support ECC RAM, they have a triple-channel memory controller, and use a different chipset (X58) in order to offer more PCIe slots. Essentially the Xeon W3xxx (used in the single-cpu MP) are Core i7-900
cpus with ECC RAM support, the Xeon X34xx (not used by Apple) are Core i7-800 cpus with ECC RAM support.
2- While geekbench and cpu benchmarks can give you an idea
of the "raw" power, they also can be flawed: simple example, in "your" cpu benchmarks the 2.80 Xeon X3460 is faster than the 2.93 Xeon X3470 (WTF?) as well as the 2.93 Core i7-940, the 2.93 Core i7-870 and even the 3.20 Xeon W3565, that's absolutly ridiculous. So. IMO, any number within 10% should not be taken as significant.
3- Why would Apple offer an headless model based on the same cpu configurations as the iMac, as they would cost less than the iMacs, hence offer less revenus/margins.
4- If you want to use plenty of PCIe cards with your cheaper Mac (Pro), the Core i7-800 family is not a good idea: the chipset only offers few free PCIe lanes if you already use a 16x graphics card. Only the X58 chipset (and higher-end Xeons chipsets) offer more PCIe lanes. The X58 chipset works with Core i7-900 series and the W3xxx series that are essensially the same cpus, in specs and prices, the Xeon having ECC support. Before you go there, the pricing of ECC RAM vs standard RAM is irrelevant in 3/4GB quantities.
5- The Core i7-800, as a line of cpus, is not that cheaper/faster than the Xeon W3xxx family:
$284 QC 2.80 Core i7-860 vs $284 QC 2.66 W3520, or the original Core i7-920
$294 QC 2.93 Core i7-870 vs $294 QC 3.20 W3565, or Core i7-960
$583 QC 3.06 Core i7-880 vs $583 6C 3.20 W3670, or Core i7-970
So, really, what do you think Apple should use for a MP (smaller or not)?
6- Since Intel offers so many different models in each family, it's sure that at some point you gonna get some overlapping. Yet as a manufacturer, you have to consider the platform as a whole, not one specific cpu vs another specific cpu...
No matter what, I would love for Apple to release a smaller rackable MP (uni-processor is fine), as long as I get a reasonable number of PCIe lanes available (either for physical PCIe slots or TB ports - each TB port using up to 4x PCIe lanes). So unless Intel releases new cpus with more integrated PCIe lanes or new chipsets that can handle more than 8 PCIe lanes, Xeon W3xxx/Core i7-900 + X58 (and their future SB versions) are still the right way to get everything you need. Even with a much smaller enclosure/PSU, numbers of bays or PCIe slots, etc. I don't expect a "xMac pricing", but starting at $1999 with a QC 3.20 W3565, would be a nice gesture.