Is vSphere Standard licensed per socket or per CPU?

Hi,

I am terribly confused around vSphere licensing, hoping someone can help.

Can anyone tell me if vmware vSphere Standard is licensed per physical socket or per physical CPU?

I bought an old server that has 4 CPU sockets in it but only one physical processor, and i was hoping to use vSphere, but someone told me it's per socket not per CPU which would mean it would be astronomically more expensive than Hyper-V which is only licensed per core (of which i only have 8). Per socket seems crazy, why should i have to pay for an empty CPU socket?

Thanks!