When the cloud is the better answer
- Email and documents. Microsoft 365 or Google Workspace do this better than a server in a closet, with backups and security handled for you.
- Your main software has a cloud version. Accounting, CRM, practice management and point of sale mostly do now.
- Nobody on staff looks after IT. A server needs updates, backups, monitoring and a plan when hardware fails. If no one will do that, it becomes a risk.
- Staff work from several places. Cloud services reach everyone without a VPN.
When a server on site makes sense
- Line-of-business software that only runs on a local Windows or Linux server.
- Large files edited all day by several people, where cloud sync is slow (video, CAD, imaging).
- Equipment on the shop floor, in a lab or in a clinic that talks to a local system.
- Steady workloads where years of cloud fees would exceed buying hardware.
- Running AI models on your own hardware for privacy; see on-premise AI.
- Keeping a local copy of cloud data, or hosting virtual machines for several small workloads.
If the only job is shared files and backups, a NAS costs less and is simpler to run.
Tower or rack
- Tower servers look like large desktop PCs. They suit an office with one server and no rack, and they are usually quieter. They take floor space and are hard to secure unless they sit in a locked room.
- Rack servers mount in a standard 19-inch rack, measured in rack units (1U is 1.75 inches). They suit a comms closet that already holds a network switch and patch panel, and make it easy to add servers, storage and a rack UPS in one place. They are often loud and need a rack deep enough for them; check the depth before buying.
- Small form factor servers and mini PCs cover light workloads such as a domain controller or a small application at a branch.
The specs that matter
- ECC memory, which detects and corrects memory errors. Standard on server platforms and the main reason a server is not a desktop PC.
- Hot-swap drive bays and hardware RAID or a proven software RAID, so a failed drive can be replaced without shutting down.
- Redundant power supplies, ideally fed from two separate circuits or UPS outputs.
- Out-of-band management (such as Dell iDRAC, HPE iLO or generic IPMI and Redfish). It lets you or your IT provider power-cycle and repair the server remotely, even when the operating system is down.
- Warranty and support. Next-business-day on-site parts service is worth paying for on a server the business depends on. Budget to replace the server after five to seven years.
- Cores and memory sized for the software vendor's requirements, with room for growth. Ask the vendor, not the hardware seller.
Licensing
Windows Server is licensed by physical processor core, with a minimum of 16 core licenses per server, plus client access licenses (CALs) for each user or device that connects. Standard edition covers a limited number of virtual machines; Datacenter covers unlimited ones. Some line-of-business and database software is licensed per core as well. More cores than you need can cost more in licenses than in hardware, so confirm licensing before choosing a processor.
Power, heat and noise
A server runs every hour of the year, so power draw adds up. ENERGY STAR certifies servers, and the server register lists certified models with their idle and active power data. Plan for:
- A UPS with software that shuts the server down cleanly before the battery runs out. Size it with the UPS sizing guide and compare models in the UPS register.
- Cooling. A closet with a door and no ventilation will overheat. Plan airflow or a dedicated cooling unit before the server arrives.
- A dedicated circuit for a rack with several servers.
- Longer outages. For work that cannot stop, see standby generators.
The costs people miss
- Operating system licenses and CALs, often a large share of the first-year cost.
- Backup software and offsite storage.
- An IT provider's monthly fee to patch and monitor the server.
- Support contract renewals after the included warranty ends.
- Electricity and cooling for five years or more.
- A faster network: a 10 Gb/s switch port for the server helps when many people use it; see the network switch guide.
Before you buy
- Write down what the server will run, and check whether a cloud version would do.
- Get the software vendor's hardware requirements.
- Choose tower or rack based on where it will live, and measure the space.
- Insist on ECC memory, hot-swap drives, remote management and on-site warranty.
- Price operating system and CAL licenses before choosing the core count.
- Plan backups, a UPS with automatic shutdown, cooling and who maintains it.
- Compare certified models in the server register.
Network racks
Affiliate linksWall-mount and floor racks for a switch, patch panel, server and rack UPS. Check the depth against the server before buying.
Tecmojo
Tecmojo 6U Wall Mount Server Cabinet IT Network Rack Enclosure Lockable Door and Side Panels Black, Cooling Fan, Standard Glass Door, 450mm Depth, for 19” IT Equipment, A/V Devices
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Tecmojo 18U Wall Mount Rack Network Cabinet for 19" IT Equipment,with Lockable Glass Door and Side Panels,Cooling Fan,Black,17.7inch Depth for AV/Computer/Electronics Equipment Data Rack
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Tecmojo 9U Wall Mount Server Cabinet IT Network Rack Enclosure Lockable Door and Side Panels Black,Cooling Fan, Glass Door, 17.7inch Depth,for 19” IT Equipment, A/V Devices
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Tecmojo 15U Wall Mount Rack,15U Rack 23.6 Inch Depth,Hold Up to 176 Lbs,Enclosed Wall Mount Rack with 2 Colling Fans,for 19 Inch Network,Server and AV Gear,Glass Door(Elite Collection)
Prices retrieved from Amazon on 2026-09-29 and may since have changed; the price on Amazon at the time of purchase is the one that applies. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. No manufacturer pays for a place in this list.