I recently purchased a VEGA FE edition card and I believe it supports SR-IOV which should, in theory allow for multiple vms to share the same card. Has anyone tried SR-IOV with unraid vm?  Any help would be appreciated.

You will have to ask @limetech if the enabling drivers have been included and configured in the kernel. Since this is the first reference to it I remember seeing on here, I doubt it. Good news is, if it's as simple as it sounds on the few pages I googled, there is a good chance it could be included easily if it's not already there. How well it works is another thing altogether though. If you want to do some research on your own, unraid is based on slackware and uses KVM to run VM's, googling those terms plus SR-IOV may shed some light on things.