That's right, you don't need a GPU to host a server. In fact, I hosted my server using a 4GB ram raspberry pi on linux, supporting 6 concurrent players at one point without a hitch. The actual server binary only ever had access to about ~2 Gigs of ram at any one time.
By GPU I meant if server also requires some GPU but seems like from your description that it doesn't.
Thank you again for the detailed answer.