That's no "high end graphics adapter" but...
Yes. any card that has those connectors for power do need both to be connected to PSU.
It may work with just one or no power connectors but only in very low mode (like in BIOS).
Beside PSU having to have two PCIe 6pin connectors it also should have at least 450 -500W depending on rest of system.
(This coming from a 70 year old/young)