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Black 2U rackmount server chassis with four front drive bays

Silverstone

Silverstone RM21-304 2U Micro-ATX Rack Server Chassis 4×3.5" Bay

SKU CH-26VK-D0WP5

2U rack chassis holds four hot-swap 3.5" SAS/SATA drives, fits Micro-ATX boards and includes three 80 mm PWM fans

  • TypeServers
  • Four 3.5" hot-swap bays with SAS/SATA backplane
  • Three 80 mm PWM fans provide active cooling
  • Auto-lock handles secure the 2U chassis in the rack
  • Micro-ATX and Mini-ITX motherboard compatibility
  • Four low-profile PCI/PCIe expansion slots supported

RM21-304 2U Rack Chassis for Micro-ATX

The Silverstone RM21-304 is a 2U rackmount server chassis designed for Micro-ATX and Mini-ITX motherboards. It provides four hot-swap bays that accept 2.5" or 3.5" SAS and SATA drives. Three included 80 x 15mm PWM fans deliver active air cooling for the internal components.

Suited for High-Density Storage Servers

This enclosure fits builders who need four drive bays with a SAS/SATA backplane supporting 6 GB/s mini-SAS SFF-8087 connectivity. It also accommodates four low-profile PCI or PCIe expansion slots. Buyers who require more than four drive bays or a different backplane interface should consider other enclosures.

Four Hot-Swap Bays with Mini-SAS Backplane

The defining specification is the four-bay hot-swap backplane that connects via mini-SAS SFF-8087 for SAS and SATA drives. This capacity and interface determine whether the chassis matches the storage topology and controller cards planned for the build.

Highlights

  • Four 3.5" hot-swap bays with SAS/SATA backplane
  • Three 80 mm PWM fans provide active cooling
  • Auto-lock handles secure the 2U chassis in the rack
  • Micro-ATX and Mini-ITX motherboard compatibility
  • Four low-profile PCI/PCIe expansion slots supported

Specifications

TypeServers

Questions about this item

Will the four hot-swap bays accept the 3.5" SATA drives I already own?

Yes, the backplane supports four 3.5" SATA drives at 6 Gb/s via the mini-SAS SFF-8087 connector.

How can I verify the three 80 x 15 mm PWM fans are spinning correctly after installation?

Connect the fan headers to the motherboard and monitor RPM in the BIOS or a hardware-monitoring utility; all three fans should report speeds under load.

Are the rails or mounting brackets included, or do I need to buy them separately?

The chassis includes an auto-lock handle for securing the 2U unit in a standard rack cabinet; no separate rail kit is mentioned.

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