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Synology DS423+ Review 2026 | 4-Bay NAS for Plex, Specs & Buying Guide

synology ds423+
Quick Answer+


Quick Answer: The Synology DS423+ (~$470) is the best 4-bay NAS for Plex and multimedia. Its Intel Celeron J4125 with Quick Sync hardware transcoding handles multiple 4K streams effortlessly. Best for: home media servers, Plex enthusiasts, Synology Photos users, and anyone prioritizing multimedia performance over raw power. Skip if: You need 10GbE, NVMe caching, or heavy Docker/VM workloads (get DS923+ instead).

The Synology DS423+ fills a specific niche: a 4-bay NAS optimized for multimedia rather than raw power. While the DS923+ gets the headlines with its AMD Ryzen CPU and 10GbE options, the DS423+ quietly excels at what most home users actually need — Plex transcoding, photo management, and reliable file storage.

This review covers everything you need to know: specifications, Plex transcoding capabilities, how it compares to the DS923+, and who should choose this multimedia-focused NAS.

DS423+ Price & Availability

ProductCapacityPrice$ / TBPrice DropBrandInterface

The DS423+ has an MSRP of approximately $470-500. This makes it roughly $50-80 less than the DS923+, positioning it as the more affordable 4-bay “Plus” option.

DS423+ Specifications

ComponentSpecification
CPUIntel Celeron J4125 (4-core, 2.0 GHz base / 2.7 GHz burst)
GPUIntel UHD Graphics 600 (Quick Sync)
RAM2GB DDR4 (expandable to 6GB)
Drive Bays4x 3.5″/2.5″ SATA HDD/SSD
M.2 Slots❌ None
1GbE Ports2x Gigabit RJ-45
10GbE Option❌ Not supported
USB Ports2x USB 3.2 Gen 1
eSATA Port❌ None (no expansion)
PCIe Slot❌ None
Max Raw Capacity72TB (4x 18TB)
Max IP Cameras30 (Surveillance Station)
File SystemBtrfs, ext4
RAID SupportSHR, RAID 0, 1, 5, 6, 10, JBOD
Hot SwappableYes
Power Consumption28W (access) / 10W (HDD hibernation)
Noise Level20.5 dB(A)
Dimensions166 x 199 x 223 mm
Weight2.18 kg (diskless)
Warranty3 years

The DS423+’s Secret Weapon: Intel Quick Sync

The Intel Celeron J4125’s integrated UHD Graphics 600 includes Intel Quick Sync Video — hardware-accelerated video encoding/decoding that dramatically outperforms software transcoding:

Transcoding TypeDS423+ (Intel QSV)DS923+ (AMD)
1080p → 1080p3-4 simultaneous streams1-2 streams
4K → 1080p2-3 simultaneous streams~1 stream (struggles)
4K → 4K1-2 streamsNot practical
HEVC/H.265 decode✅ HardwareLimited
HDR tone mapping✅ SupportedLimited

This makes the DS423+ significantly better for Plex, Jellyfin, and Emby media servers — even though the DS923+ has a faster CPU on paper.

Plex Performance: The DS423+ Shines

Hardware Transcoding Capabilities

With Plex Pass (required for hardware transcoding), the DS423+ delivers:

  • Direct Play: Unlimited simultaneous streams
  • 1080p transcodes: 3-4 simultaneous
  • 4K HDR to 1080p: 2-3 simultaneous (with tone mapping)
  • 4K transcodes: 1-2 simultaneous

Codec Support

  • ✅ H.264 encode/decode
  • ✅ HEVC/H.265 decode (8-bit and 10-bit)
  • ✅ HEVC encode
  • ✅ VP9 decode
  • ✅ HDR10 tone mapping

Real-World Plex Usage

A typical family scenario:

  • Living room TV: Direct play 4K (no transcode needed)
  • Kid’s tablet: 720p transcode
  • Phone on cellular: 480p transcode
  • Friend streaming remotely: 1080p transcode

The DS423+ handles all four simultaneously without breaking a sweat — something the DS923+ would struggle with.

Synology Photos Performance

Beyond Plex, the DS423+ excels at Synology Photos:

  • Facial recognition: Hardware-accelerated processing
  • Thumbnail generation: Faster with Intel GPU
  • Video preview: Quick scrubbing through video files
  • Object detection: AI-powered sorting

Photo library indexing and facial recognition run noticeably faster on Intel-based units compared to AMD.

DS423+ vs DS923+: The Critical Comparison

This is the key decision for most 4-bay NAS shoppers:

FeatureDS423+ (~$470)DS923+ (~$550)
CPUIntel Celeron J4125AMD Ryzen R1600
Plex Transcoding✅ Excellent (3-4 streams)⚠️ Limited (1-2 streams)
RAM2GB (max 6GB)4GB ECC (max 32GB)
10GbE Option❌ No✅ Yes
NVMe Slots❌ None✅ 2x M.2
PCIe Slot❌ None✅ PCIe 3.0 x2
Expansion❌ 4 bays only✅ Up to 9 drives
ECC Memory❌ No✅ Yes
Best ForPlex, multimediaDocker, VMs, 10GbE

Choose DS423+ If:

  • Plex/media server is your primary use case
  • You want best-in-class hardware transcoding
  • Budget is a factor (~$80 savings)
  • Synology Photos is important to you
  • 4 bays are sufficient (no expansion needed)
  • Gigabit Ethernet meets your needs

Choose DS923+ If:

  • You want 10GbE networking
  • Running Docker containers or VMs
  • Need more than 6GB RAM
  • Want NVMe caching/storage
  • May need to expand beyond 4 bays
  • ECC memory is important

Limitations to Consider

No Expansion Capability

Unlike the DS923+ (expandable to 9 drives), the DS423+ is fixed at 4 bays. If you outgrow 4 drives, you’ll need a new NAS. Plan your capacity needs carefully.

Limited RAM Ceiling

Maximum 6GB RAM limits heavy Docker/VM workloads. The stock 2GB is fine for Plex and file sharing, but upgrade if running multiple services.

No NVMe Caching

Without M.2 slots, you can’t add SSD caching. Random I/O performance depends entirely on your HDDs (or using 2.5″ SSDs in the main bays).

Stuck at Gigabit Ethernet

No 10GbE option means ~115 MB/s maximum network throughput. For most home users this is fine, but video editors working with large files may feel constrained.

Ideal Use Cases

Home Media Server

The DS423+ is purpose-built for media:

  • Plex Media Server: Hardware transcoding for multiple users
  • Jellyfin/Emby: Alternative media servers with Intel QSV support
  • Video Station: Synology’s native media app
  • Audio Station: Music library management

Photo Library Management

Synology Photos performance benefits:

  • AI-powered facial recognition
  • Fast thumbnail generation
  • Google Photos migration alternative
  • Mobile app backup

Family Backup Hub

Simple, reliable backup for the household:

  • Synology Drive: File sync across devices
  • Active Backup for Business: PC/Mac backup
  • Time Machine: Mac backup support
  • Cloud Sync: Backup to/from cloud services

Recommended Drives for DS423+

For media storage, capacity matters. Consider 8TB+ drives to maximize your 4-bay setup. WD Red Plus or Seagate IronWolf are ideal choices.

See our complete Synology Compatible Drives Database for verified compatibility.

RAID Configuration Recommendations

ConfigurationRAID LevelUsable CapacityBest For
4× 4TBSHR12TBBudget setup
4× 8TBSHR24TBTypical home media
4× 12TBSHR36TBLarge library
4× 16TBSHR48TBPower user
4× 8TBRAID 616TBMaximum protection

Recommendation: Use SHR for best capacity utilization with 4 drives. Consider RAID 6 for critical data where rebuild protection matters more than capacity.

Use our RAID Calculator to plan your configuration.

Frequently Asked Questions

Is the DS423+ good for Plex?

Yes — the DS423+ is one of the best NAS options for Plex. Intel Quick Sync hardware transcoding handles 3-4 simultaneous 1080p streams or 2-3 4K-to-1080p transcodes. It significantly outperforms AMD-based models like the DS923+ for Plex use.

DS423+ vs DS923+: Which is better?

It depends on your use case. DS423+ is better for Plex transcoding and multimedia (Intel Quick Sync). DS923+ is better for Docker/VMs, 10GbE networking, NVMe caching, and expansion to 9 drives. Choose DS423+ for media; choose DS923+ for power user features.

Can I expand the DS423+ beyond 4 drives?

No. The DS423+ does not support expansion units — it’s fixed at 4 bays. If you anticipate needing more than 4 drives, consider the DS923+ (expandable to 9 drives) or DS1522+ (expandable to 15 drives).

Does the DS423+ support 10GbE?

No. The DS423+ has no 10GbE option — it’s limited to dual Gigabit Ethernet (~115 MB/s max). If 10GbE is important, choose the DS923+ which supports the E10G22-T1-Mini upgrade module.

How much RAM should I add to the DS423+?

Stock 2GB is fine for Plex and basic file sharing. Upgrade to 4-6GB (max supported) if running multiple DSM applications simultaneously. For heavy Docker workloads, the DS423+ may not be ideal due to its 6GB RAM ceiling.

Does the DS423+ have NVMe slots?

No. The DS423+ has no M.2 NVMe slots — it cannot use SSD caching. If NVMe caching is important for your workload, consider the DS923+ which has two M.2 slots.

Verdict: Who Should Buy the DS423+?

✅ Buy DS423+ If…❌ Skip DS423+ If…
Plex is your primary use caseYou need 10GbE networking
Hardware transcoding mattersYou want expansion capability
Synology Photos is importantRunning heavy Docker/VMs
Budget is a priorityNeed more than 6GB RAM
4 bays are sufficientWant NVMe caching

Our recommendation: The Synology DS423+ is the best 4-bay NAS for home media servers. Its Intel Quick Sync hardware transcoding makes it ideal for Plex, Jellyfin, and Synology Photos — outperforming the more expensive DS923+ in these specific workloads. Choose it if multimedia is your priority. If you need 10GbE, expansion, NVMe caching, or heavy Docker/VM workloads, the DS923+ is the better choice despite weaker transcoding performance.

Related Resources


Last Updated: February 2026 | Prices and specifications verified

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