So, around $9500 presuming you already have a suitable power supply and case and to jam it in (call it another $500), plus mouse and keyboard. That monitor I selected isn't going to be any kind of rival to what Apple chooses, I'd better confess.
Call it $10,000 for a comparable PC workstation running MS Windows, or a fizz-bzzt-bang-pop Linux system with dubious driver support and reliability.
Finally, I'm unsure that the components I selected above will meet (much less exceed) the hardware that Apple will integrate into the new iMac Pro. My guess is that my list is full of 'second best' items. Back in 2015, the new Retina MacBook Pro hardware couldn't be replicated in the PC world at any price because the components weren't entirely for loose retail sale to consumers. Don't forget Apple gets to work with OEMs to tune onboard chips and circuitry with their own hardware code.
PRECISELY.
Apple is a SYSTEM company. Hardware and software that are developed together as an integrated, coherent whole entity.
During much of my engineering career I was a "systems" engineer, just as much as a hardware engineer, and more than I was a software engineer. It's the hardest of the three, if you do it right.
A box of hardware components can make a hardware box, and a generic operating system like Windows can operate that box, but it's not like the OS and that hardware were designed from the get-go to work as an integrated unit.
When I pony up my hard-earned cash for a piece of Apple gear, it's because it was designed to work as a whole, not as a bunch of separate parts that were convinced to cooperate with each other using a hammer, spit and piano wire, and prayer.
But I say this proudly as a 30-year user of Windows:
The outstanding triumph of Windows is that it works reasonably well on the incredibly heterogeneous, and often miscellaneous and haphazard, collections of components that people install it on.There is plenty of room in the world for both approaches. But let's not make the mistake of trying to compare them on the basis of simple things like price and hardware specs. The approaches are apples and oranges.
They list the RAM as 2666 MHz. The only Intel Xeon processors that can drive that fast a RAM are the new Kaby Lake generation Xeon Gold and Platinum processors. Apple gives another hint in the TurboBoost speed of 4.5GHz.TurboBoost speed is at most half again in addition to the regular clock speed. Ergo, the standard clocking of the processor has to be around 3GHz or so. The 8 core Xeon Gold processor runs at 3.2 GHz while the 18 core Xeon processor runs at 3.0 GHz. Both support 2666 MHz ECC RAM. . . But the Platinum has too many cores.
. The 2 ½ year old (Jan. 2015) $3400 version 3, 2.4GHz Xeon E5 processor you selected for your top end is nowhere nearly in the ballpark of being the equivalent of either of those processors. That 2.4 GHz could probable TurboBoost to only 3.4 GHz, and the ECC RAM is slower. I suspect that the retail cost of these new processors is easily double what you quoted for that much older version 3 E5. Last years' E5s (now called Gold) that come close but don't support 2666 MHz RAM are over $7700 per unit according to Intel! The Gold and Platinum processors are not yet priced.