The following table lists the differences between the Blade Servers and Rack Servers:

Blade Servers Rack Servers
Sits into UCS blade chassis Sits on a rack
Can’t operate independently. Requires UCS infrastructure Can operate independently
Connects only to UCS Fabric Interconnect Can connect to any Ethernet switch including UCS Fabric   Interconnect
Managed from the UCS Fabric   Interconnect by Cisco UCS Manager Features Cisco Integrated Management Controller (CIMC) and   thus can be managed independently or from Cisco UCS Manager if connected to a   UCS Fabric Interconnect
Supports RAID 0 and 1 only Supports built-in RAID 0 and 1 for SATA drives. RAID 0, 1, 5, 6, and 10 support through a PCIe LSI MegaRAID   Controller
Supports Gigabit Ethernet Mezz cards and Converged Network   Adapter Mezz cards Supports Gigabit Ethernet PCIe cards, Converged Network   Adapter PCIe cards and Fibre Channel HBA PCIe cards.
Supports up to two front-accessible,   hot-swappable SAS drives for local storage Supports up to 4 front-accessible,   hot-swappable, internal 3.5-inch SAS or SATA drives
No support for PCIe slots Support for up to 2 PCIe 2.0 slots
No support for optical drive Optional front panel optical drive for   CD and DVD media