RAM & Storage Compatibility for Synology RS4021xs+
The Synology RS4021xs+ is a 16-bay NAS from the RackStation range. It uses ECC DDR4 memory with 4 RAM slots, upgradeable to a maximum of 64GB. It also supports 2x M.2 NVMe for SSD caching to accelerate frequently accessed data.
Memory Specifications
| Specification | Details |
|---|---|
| Memory Type | ECC DDR4 |
| RAM Slots | 4 |
| Max RAM | 64GB |
| RAM Speed | 2666 MHz |
| Drive Bays | 16 |
| SSD Cache | 2x M.2 NVMe |
| ECC Support | Yes |
Recommended RAM Upgrades
Best RAM: Samsung ECC DDR4-2666 SODIMM 16GB
ECC memory is recommended for enterprise NAS devices to prevent data corruption. Tested compatible with Synology systems.
Official Synology Memory Module
The official Synology-branded memory module guarantees compatibility but typically costs more than third-party options.
SSD Cache Recommendations
The Synology RS4021xs+ supports 2x M.2 NVMe for SSD caching. Adding NVMe cache SSDs significantly improves random read/write performance for frequently accessed files.
Best Cache SSD: WD Red SN700 500GB NVMe
Designed specifically for NAS use with high endurance ratings. Optimised for 24/7 operation and caching workloads.
Recommended Hard Drives
Best NAS HDD: Seagate IronWolf 8TB
Purpose-built for NAS with AgileArray technology, vibration sensors, and 3-year Rescue Data Recovery. Rated for 24/7 operation.
Frequently Asked Questions
Can I upgrade the RAM in the Synology RS4021xs+?
Yes, the Synology RS4021xs+ has 4 RAM slots and can be upgraded to a maximum of 64GB.
What type of RAM does the Synology RS4021xs+ use?
The Synology RS4021xs+ uses ECC DDR4 running at 2666 MHz. ECC (Error-Correcting Code) memory is required for data integrity.
Related Synology Upgrade Guides
- Synology RS2423RP+
- Synology RS3621xs+
- Synology RS2423+
- Synology FlashStation FS6400
- Synology FlashStation FS2500
- Synology Upgrade Guide
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