One of the advantages of using a Proof Of Stake (POS) consensus protocol like Cardano's.
Is that the servers doing the block validation don't need to be big specialized machines. In fact a "normal pc" could work to operate your stakepool. What is more important is to have reliable and redundant components.
Minimal stakepool equipment
- 4 GB of RAM
- Good network connection and about 1 GB of bandwidth / hour
- A public ip4 address.
- Note: Processor speed is not a significant factor
For Daedalus users please see System Requirements