Not sure if i understood well your suggestions about the new Threadripper 2 cpu, let see if i can help you to get some clarifications:
To be honest i did not found any related new regarding your first point, until today.
The only news i could find out about the bios capacity issue come out today, i.e see Techpowerup.
This limited bios chip capacity used by manufacturers seems related on AM4 socket, from what report the article.
The news explain that the issue of bios capacity would be resolved dropping support of old Bristol Ridge cpu, the Ax-9xxx series.
Since Threadripper have his own X399 platform and socket, not sure this bios capacity issue would also apply to the new Threadripper 2, but who knows.
Not sure i understood the source voltage problem idea, i mean you would maybe need a bios update to support Threadripper 2 on previous X399 boards.
As AMD did when the 2xxx Ryzen series launched, to get support on the already existing x3x0 motherboards.
Personally i would not plug a cpu without be sure to have the proper motherboard bios support for it anyway.
If you a speaking about power consumption requirement for Threadripper 2, i think the 32 cores would cap at 250Watt by specs.
Maybe some existing X399 boards would not meet the power requirement for the 32 cores, hence it's not possible on these boards to add power connectors.
It would better buy a new motherboard with a power stage VRM able to sustain the new Threadripper2 power requirement, depending which model/vesrion you are looking for
Hope it help you, not sure where you got these interesting mixed informations, but would be glad you try to explain them. ^^
Yes sorry for that mix, I heard different news for each of them problems, the fact that regular pins in the motherboard can't handle 250W, unless some standard power cable voltage and amps would change which is very very unlikely to happen . The bios problem was more visible and of course the cooling problem, so it kinda mixed up. butyeah most of the thing you said where true. The explanation is this:
First when someone buys a specific threadripper gen 1 motherboard, it has a very simple bios jsut to start the PC and get in the OS, through OS the customer should flash the bios of it's processor, whether it's gen 1 or gen2. Other thing is that they can change the voltage that the socket provides depending on the processor that it has.
Overall the idea of dropping the support for Bristol which resolves the problem the best way.(though not sure how many people are still using Bristol-based processors, if they are very low then it's worth it.)
Unfortunately there is nothing that can be done if the motherboard do not meet the power requirement for the 32 cores.
But i saw that TR2 will also ship with lower cores versions like 28,24,22,18 cores, hence less power hungry.
So even if one could not fit a 32 cores due to the power requirement, one could still upgrade quite safely to the 18 or even 22 cores.
It is, at least, a positive thing that the user could, at least, upgrade his cpu without changing the whole system.
For the bios issue, i would hope that TR would not meet this issue with only a couple of cpu's revisions.
I could maybe imagine this be an issue when we would hit, for example TR7, with the bios not capable to hold too many cpu versions.
If the motherboard manufacturers do not decide to upgrade the bios capacity with a bigger chip, in the future.
I mean it could be a non issue on new coming motherboards, if the manufacturers really wanted so!
As said on AM4, for now, only the the old Bristol Ridge cpu support was dropped to free space into the bios.
I would say that cpu bios support is not an easy thing, especially when dealing with different refresh of the cpu's.
Trying to keep the same system with another cpu seems to be a nice feat nowadays and this do not goes without some limitations.
I think the users should also do their part seeking a minimum of knowledge and support when offered to update the cpu on an existing motherboard.
Usually, if the manufacturer release good procedures and the customer seek basic knowledge about, the cpu upgrade is done without issues.
About the cooling, i suppose the already existing and new coolers would be fine for the new TR2 series, depending the number of cores obviously.
I would still wait the cpu come out to leverage the cooling requirement, before think to build and buy the rig.
I would suppose that a liquid cooled solution would be the best, to take maximum profit of the 32 cores version tho.