I was thinking, anybody having there hands on a new MacPro (the late 2013), would it be possible -in time- to swap the CPU from a new MacPro?
Its the CPU soldered to the motherboard?
Looking forward for your thoughts.
While there is no teardown of the 2013 MacPro yet, digging into Intel's Ark DB might be useful.
For example the i7 processor used in the MacBook Pro Retina late 2013 is a 4750HQ registered as using the BGA "socket" (Ball grid array) which is synonym of soldered to the mainboard.
For the MacPro Apple tells us there is either a 3.7Ghz w/ 4cores or a 3.5GHz w/ 6cores or a 3.0GHz w/ 8-cores or a 2.7GHz w/ 12-cores. All the processors that have these specs in ark are listed to only using the FCLGA2011 socket (see here the Xeon E5 v2 spec sheet).
So to me it's pretty sure that yes the cpu is not soldered to the mainboard and is therefore upgradable.
It certainly will be upgradeable, but to what, exactly? Only other processors of the same architecture (in this case, Ivy Bridge-EP - you won't be able to upgrade it to, say, Haswell, and it will be unlikely that there is a change in Mac Pro architecture such that a newer chipset will be used, provide significant advantage over what you're using now, and still be compatible with the current model).
More details and links, from a couple of paragraphs stolen from my own blog post written in January:
In spite of many published assumptions to the contrary, the CPU is removable and upgradeable (details here, here, here, and here). However, the one socket is Ivy Bridge-EP, so you'd only be able to move up to a higher number of relatively equivalent cores later, not to an entirely new chipset like Haswell. In the MacRumors piece, OWC successfully replaced the E5-1650 V2 (6 cores, 3.5-3.9 GHz, 12 MB cache) with the E5-2667 V2 (8 cores, 3.3-4.0 GHz, 25 MB cache). Currently this may not seem like a fantastic deal, as the 2667 has an MSRP just over $2,000 – though the Apple upgrade from 6 to 8 cores (likely the E5-1680 V2, with the same cores and cache, but lower clock speed of 3.0-3.9 GHz) is $1,500, and you don't get to keep, sell or re-purpose the 6-core chip. Presumably you would only do this anyway when Ivy Bridge prices fall much further and/or when your warranty is up.
Personally, I wouldn't risk it – just buy the processors you need now. It's not like CPU clock speeds are on the verge of smashing the 4.0 GHz barrier anyway, or there are significant core count increases coming soon, and I think the process of swapping out this specific CPU in this specific machine a year or two down the road is going to be a lot more complex than you might expect. That all said, I don't remember ever wanting or needing to replace the CPUs in a workstation – usually you can't jump chipsets, and by the time you can justify that change, there are probably plenty of other things you could upgrade as well. In the Mac Pro space, this could be quite some time away.