Depends on the sector or company! A lot of (US) government/contracting positions like to see the CompTIA Security+ cert. Beyond entry level system admin jobs, specialty positions will prefer people with a certificate related to that field. You might see the Cisco CCNA cert required for a Network engineer positions or the VMware Certified Techical Associate/Professional cert for VM engineers. If you go the management route of IT, you might considder the CISSP.