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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

  • Product 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.

How it compares

Measured against everything we stock in Rack & Tower Servers, at today’s prices. Recalculated every night.

Price $576.99
Cheaper than about 91% of the 17,641 comparable items (median $1,910.99).

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Specifications

Product
Product 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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