From this HW generations, only to HEDT platforms like X79/X99 motherboards.
IOMMU /SR-IOV groups
EDIT:
They do since they have their own “PLX” IC chipset and manage the PCIe lanes, this of course on a slot x16/x8 available lanes.
I think this solution is only valid for someone that has a high-end board, with a spare PCIe3.0 x16 slot that will not interfere (split) his high-end GPU on slot x16_1…
Boards with enough slots, i would advise an option of 2 separate PCIe NVMe adapters if looking for a boot/storage configuration, but the main issue on this old boards is trying to get them at least working with NVMe @ 3.0x4 on the available slots and still not to split our GPU… right? Damm hard as most of them get the rest of the slots only as PCIe2.0x4
But definitely not money to spend on a “Plus” board…my opinion only.