The Synology RS3621xs+ is a 12-bay NAS from Synology in the RackStation range. It comes with 8GB of DDR4 ECC RDIMM RAM (upgradeable to 64GB) and supports 3.5-inch SATA HDD/SSD drives. This guide covers compatible RAM and storage upgrades with our top recommendations.
Synology RS3621xs+ Specifications
| NAS Model | Synology RS3621xs+ |
| Brand | Synology |
| Series | RackStation |
| Drive Bays | 12 |
| Processor | Intel Xeon D-1541 |
| Default RAM | 8GB |
| Max RAM | 64GB |
| RAM Type | DDR4 ECC RDIMM |
| RAM Slots | 4 |
| Drive Compatibility | 3.5-inch SATA HDD/SSD |
| Network | 4x 1GbE + 2x 10GbE |
| Release Year | 2021 |
Compatible RAM for Synology RS3621xs+
The Synology RS3621xs+ ships with 8GB and can be upgraded to a maximum of 64GB. It uses DDR4 ECC RDIMM SO-DIMM modules (4 slots).
Recommended RAM Upgrades
| Capacity | Module | Buy |
|---|---|---|
| 4GB | Crucial DDR4-2666 4GB SO-DIMM | Check Price |
| 8GB | Crucial DDR4-2666 8GB SO-DIMM | Check Price |
| 16GB | Crucial DDR4-2666 16GB SO-DIMM | Check Price |
Compatible Storage Drives
The Synology RS3621xs+ has 12 drive bays supporting 3.5-inch SATA HDD/SSD. Here are our top drive recommendations:
Recommended NAS Drives
| Capacity | Drive | Buy |
|---|---|---|
| 4TB HDD | Seagate IronWolf 4TB NAS HDD | Check Price |
| 8TB HDD | Seagate IronWolf 8TB NAS HDD | Check Price |
| 16TB HDD | Seagate IronWolf Pro 16TB NAS HDD | Check Price |
| 1TB NVMe | Samsung 970 EVO Plus 1TB M.2 NVMe | Check Price |
Setup Tips
- Use NAS-rated drives: Always use drives designed for NAS use (e.g. Seagate IronWolf, WD Red Plus) for reliability and vibration resistance.
- RAID configuration: For data protection, use RAID 1 (mirroring) for 2-bay units or RAID 5/SHR for 4+ bay units.
- RAM upgrade: Upgrading RAM improves multitasking, virtualisation and app performance. Use Synology-compatible modules.
- Network: Connect via Ethernet for best performance. This model supports 4x 1GbE + 2x 10GbE.
Frequently Asked Questions
What is the maximum RAM for the Synology RS3621xs+?
The Synology RS3621xs+ supports up to 64GB of DDR4 ECC RDIMM RAM.
How many drive bays does the Synology RS3621xs+ have?
The Synology RS3621xs+ has 12 drive bays supporting 3.5-inch SATA HDD/SSD.
What drives are compatible with the Synology RS3621xs+?
The Synology RS3621xs+ supports 3.5-inch SATA HDD/SSD. We recommend NAS-rated drives like the Seagate IronWolf or WD Red Plus series.
Related Synology Upgrade Guides
- Synology RS4021xs+
- Synology RS2423RP+
- Synology RS3621xs+
- Synology RS2423+
- Synology FlashStation FS6400
- Synology Upgrade Guide
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Prices from PCHub.UK via ComputersDeal. As an affiliate, we may earn from qualifying purchases. Prices updated 2026-04-10 13:15:58.