I'm looking to buy an new workstation but have a BOOT question.

The T3620/T3630 models give you the preconfigured option of booting via SSD. Question is which one. The M.2 SSD directly fixed on the motherboard or via a M.2 SSD module on a PCIe card? A assume these models come with the latter option. 

Secondly, am I correct that you must be able to boot from the M.2 SSD on the motherboard freeing up a PCIe slot.

thx for comments