Thunderbolt Enabling on UEFI and then this "Unique ID" Selection?

[arda21]

After updating my UEFI / BIOS, I realized that in "System Browser", it didn't see Thunderbolt 2 AIC card that is on my PCIE 2, (motherboard is AsRock Extreme4 x99)

So I went back into UEFI, on Advanced Chipset settings there is a switch that was put back to "Disabled" on Internet Thunderbolt Tech switch,

Enabling is what I needed to do, but then another settings comes up when You enable, it has 4 choices
1-Legacy Mode
2-Unique ID
3-One Time Saved Key
4-DP++ only

now it is by default on Unique ID as when you first enable the Thunderbolt,
I looked into the manuals for this, I didn't find anything about what I need to choose,
I am attaching the photos to show you the menu indeed:

Does anyone point me to the right direction to make sure my thunderbolt adapter function correctly?

 

[Lutfij]

If your thunderbolt adapter is powering a DP display then you should set it to DP++ while I'm sure Unique ID will do it for your needs. You can also set it to Legacy Mode if all else fails. Might I ask your full system's specs and the thunderbolt cards operations?