But the prices of the 2620 and E5620 are both ~$400. Where does the 294 come from? So What we have is $400 + Apple tax and the price increase appears to be about $500. So it does seem possible.
Sorry. My goof. Was looking at a cpu-world price list and snagged the 2609's by mistake. Yeah. ( 612 - 406 = 206 ) If they the don't round up to nearest hundred and skip the 30% tax its $400. [ They are still eating increase from the normal practices but it is small. ]
Personally, I throw the extra money at 128GB mSATA SSD and a embedded GPU ( same as what top iMac gets with 1GB , or 2GB if it fits, VRAM ).
The SSD would help make up for the relatively low 2GHz base rate on the 2620's. It certainly has that impact on the MBA's. I think all Mac Pro could use the boost as part of the default configuration. Essentially, it is moving an old XServe feature down to the Mac Pro. There is a built in SSD card slot. All the better now that there is a standard for these.
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Like the old XServe equivalent it is useful in server configs too. ( since the Mac Pro has those duties too). They could reuse MBA mSATA devices to can hit price point (since part of volume buy supply chain. ) .
The GPU solves the "need a Display Port signal for Thunderbolt" problem. [ could take a GPU from an iMac perhaps next to "top end" model and add 1GB , or 2GB if it fits, VRAM. At least 1GB to make it viable as limited, yet viable, OpenCL limited workhorse. ] The dual package Mac Pros with E5's have a gut of PCI-e lanes. It would make alot of sense to put them to use solving the "Thunderbolt problem".
Both of those could be around $200 (maybe tough for provide 2GB of VRAM for $200, but the SSD definately should be under. ) .... hence the $400 price bump.
However, yeah some folks are going to be "spooked" by the E5 2620's base clock rate being "just" 2GHz. To those who buy on MHz ratings that's a negative. For people with core scalable workloads the additional four cores ( versus the 5620 ) should make up for the 16% drop in base rate.
The 2630 does have the higher max speed and the four additional cores over the 5620 ... so overall better even without the SSD boost.
That is a possibility too. Maybe they are making room for a smallish boot SSD + HDD, or a better GPU, or a reasonable amount of RAM standard, or some combination of all three. We'll see shortly it seems.
I don't think "better" GPU.... think dual GPUs.
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The standard config would be you get the embedded one to "solve" the TB problem and still get a regular GPU to hook displays to. The sever ( or CTO ) configs you can dump the PCI-e GPU card.
RAM wise I would expect four 1GB DIMMs. One for each memory controller. Apple knows most of you are going to buy 3rd party.
I'll be surprised if it four 2GB DIMMs, but that would certainly help with the folks who grumble about limited value.