How Well Does the Synology DS423+ NAS Perform as a Plex Media Server?
The attraction of having control over all your movies, TV shows, music, and personal videos, in the sleek and organized way popularized by streaming giants like Netflix, Disney+, and Prime Video, cannot be denied. With the rise of streaming platforms, however, comes the growing cost of monthly subscriptions and the uncertain ownership of the content. Even if you purchase digital movies or TV shows from online stores like Amazon Video, you still face the challenge of finding storage space and the risk of losing access if the platform loses its license. Having a Plex media server that offers a premium and accessible user interface, without the need for subscriptions, is a key reason why many home and prosumer users choose to invest in one. However, it’s important to note that not all NAS drives are created equal in terms of compatibility and performance with Plex. In this article, I will share my experience using the DS423+ NAS as a Plex media server, to help you make an informed decision on whether it’s worth storing your 4K multimedia content on it in 2023.
Note – If you are unfamiliar with the Synology DS423+ NAS, but you want to learn more about it, what else it can do and whether it is good for more than just Plex, you can watch my video review below:
What is the Hardware of the Synology DS423+ NAS Drive?
The Synology DS423+ NAS drive is structurally similar to most personal computers and laptops, as it features a CPU, memory, and storage. However, it boasts components that are designed to be more energy-efficient and provide optimal performance for 24/7 usage, with a greater emphasis on storage-related applications. On the other hand, the hardware in a PC or laptop is geared towards running general applications, with storage services being relatively basic. The DS423+ NAS is equipped with a popular mid-range server CPU, DDR4 memory, and can accommodate both Hard Drives and SSDs using SATA connections. Although the specifications of Synology NAS drives are not directly linked to Plex, it is important to understand the hardware specifications relevant to Plex when considering the DS423+ NAS. Below, I have compiled a list of the hardware specifications of the DS423+ that play a significant role in its compatibility and performance with Plex:
- CPU: Intel J4125 Celeron 4-Core CPU, 2.0-2.7Ghz
- Embedded Graphics: Yes
- Memory (Quantity & Maximum): 2-6GB DDR4
- Number of Storage Bays: Four
- M.2 NVMe Caching Bays: x2 (Caching Only)
- Network Connectivity: 2x 1GbE
Next, let’s quickly touch on how we measure how good/bad the Synology DS423+ NAS is for Plex Media Server.
Understanding the Plex Media Server Tests of the Synology DS423+ NAS
Important Terms to Understand in Plex/NAS/Multimedia that will make the DS423+ NAS Plex Tests Easier to Understand.
- SD, 160p, 240p, 480p, 720p, 1080p, 4K : The resolution refers to the level of detail at which media is displayed, ranging from SD to 160p, 240p, 480p, 720p, 1080p, and 4K. The higher the resolution, the more pixels are present, which is determined by the quality of the original recording. Displaying high-resolution media, such as 1080p and 4K, puts a heavier load on the NAS hardware. NAS devices with limited graphics capabilities or no graphics at all may struggle to play 4K media seamlessly or not play it at all. It’s important to keep in mind that just because a NAS brand, such as Synology, claims that their latest NAS is capable of natively playing 1080p or 4K media (natively meaning through their own software, client tools, and/or DLNA), this does not guarantee that the DS423+ NAS will perform the same way with Plex. As Plex is a third-party tool, it may have different requirements and limitations.
- Transcoding, Encoding, Decoding: Transcoding, encoding, and decoding are various terms used when a media file needs to be transformed to be better suited for a specific device, internet connection, or hardware. When accessing media locally, transcoding may not be necessary, unless your files are mainly H.265/HEVC based. However, when accessing media from remote locations with limited bandwidth, weaker internet connection, or smaller devices, you may want to access the media in lower quality. This is where transcoding, or real-time encoding, comes in handy. Keep in mind that transcoding is one of the most demanding tasks for a NAS. To utilize the full resources of the NAS CPU, including its embedded graphics, you may need to enable the “Make My CPU Hurt” option in the encoder menu of the Plex NAS settings menu, which may require a Plex Pass subscription depending on the NAS.
- H.264, HEVC, H.265: The compression techniques H.264, HEVC, and H.265 are used to make large media presentations suitable for viewing on home devices. While H.264 is widely supported by all devices, not all have permission or a license to play H.265/HEVC, as the licensing and patents for H.265/HEVC are complex, expensive, and spread across multiple providers. This can lead to the need for automatic conversion/transcoding of H.265/HEVC media into H.264, which consumes more system resources. The Synology NAS drive, like the rest of the Synology NAS range, does not come with HEVC support by default.
- Bitrate:Bitrate refers to the quantity of data that is processed per unit of time, typically expressed in megabits per second (Mbps) for video and kilobits per second (kbps) for audio. The higher the bitrate, the better the quality and resolution of the media tends to be.
For more information on the most important terms to understand when discussing/researching a NAS as a Plex Media Server can be found in my video below:
If you have any further questions, you can use the free advice section at the bottom of the page and ask Eddie and me directly.
How was the Synology DS423+ NAS Tested in Plex?
The setup for testing the DS423+ NAS for Plex was as follows:
- The Synology DS423+ NAS was accessed over a 1GbE network, however in order to test how the NAS would cope with transcoding/encoding, I would force the Plex Player client to transcode the file manually
- The DS423+ NAS was used in the default CPU+Memory state that the base model arrives in (no upgraded memory or upgraded caching media)
- Tests were performed one after the other with a short break between each test, so you might see the tail end of the previous test on a CPU graph, but I have pointed at the are of the % utilization that is important as per each test.
CLEAR PASS indicates successful file playback with enough resources for the NAS to handle other tasks, while PLAYED BUT HIGH CPU % signifies that the file played, but consumed significant system resources. FAIL AND-OR DID NOT PLAY means the file did not play or playback was choppy. To view the full video of the Plex tests performed on the Synology DS423+ NAS, watch the video below (warning: long). Or, you can scroll down to see individual test results and which ones succeeded and which ones failed.
What % System Resources did the Synology DS423+ NAS Use in Plex when Idle?
The Plex Media Server app requires a portion of system resources even when not playing multimedia, to ensure quick playback from the Synology NAS when requested remotely. While 2 cores and 2GB of memory are ideal for best performance, some NAS also reserve resources for system use. Knowing the amount of system resources consumed by the Synology DS423+ NAS when Plex is idle can provide insight into available power for playback. Here’s a screenshot of the DS423+ when Plex is running but no media is being accessed.
Synology DS423+ NAS Plex Test – UHD 4K 10bit 16mbps HEVC H.265 MKV
Here is how the Synology DS423+ NAS Plex Test – UHD 4K 10bit 16mbps HEVC H.265 MKV File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 2 – Synology DS423+ NAS Plex Test – IMAX 4K UHD H.264 8bit 40Mbps MKV
Here is how the Synology DS423+ NAS Plex Test – IMAX 4K UHD H.264 8bit 40Mbps MKV File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 3 – Synology DS423+ NAS Plex Test – IMAX 4K H.264 24FPS 40Mbs MKV
Here is how the Synology DS423+ NAS Plex Test – IMAX 4K H.264 24FPS 40Mbs MKV File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 4 – Synology DS423+ NAS Plex Test – IMAX 4K 10bit 80Mbps 10bit MKV
Here is how the Synology DS423+ NAS Plex Test – IMAX 4K 10bit 80Mbps 10bit MKV File Performed:
RESULT: FAIL AND-OR DID NOT PLAY
Extra Notes: None
Plex Test 5 – Synology DS423+ NAS Plex Test – H.264 8bit 16Mbps MP4
Here is how the Synology DS423+ NAS Plex Test – H.264 8bit 16Mbps MP4 File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 6 – Synology DS423+ NAS Plex Test – 4K UHD H.265 HEVC 8bit 60Mbps MKV
Here is how the Synology DS423+ NAS Plex Test – 4K UHD H.265 HEVC 8bit 60Mbps MKV File Performed:
RESULT: CLEAR PASS / PLAYED BUT HIGH CPU % / FAIL AND-OR DID NOT PLAY
Extra Notes: None
Plex Test 7 – Synology DS423+ NAS Plex Test – 4K H.264 12Mbps 24FPS MP4 Test
Here is how the Synology DS423+ NAS Plex Test – 4K H.264 12Mbps 24FPS MP4 Test File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 8 – Synology DS423+ NAS Plex Test – 4K UHD H.265 HEVC 8bit 29Mbps MKV
Here is how the Synology DS423+ NAS Plex Test – 4K UHD H.265 HEVC 8bit 29Mbps MKV File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 9 – Synology DS423+ NAS Plex Test – 4K UHD H.264 8bit 32Mbps MKV
Here is how the Synology DS423+ NAS Plex Test – 4K UHD H.264 8bit 32Mbps MKV File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Plex Test 10 – Synology DS423+ NAS Plex Test – 4K H.264 8bit 32Mbs MKV
Here is how the Synology DS423+ NAS Plex Test – 4K H.264 8bit 32Mbs MKV File Performed:
RESULT: CLEAR PASS
Extra Notes: None
Is the Synology DS423+ NAS Any Good outside of Plex and Where Can I buy It?
If you are interested in learning more about the Synology DS423+ NAS Drive, I am pleased to confirm that the review here on NASCompares is already live and you can find out more about this device below.
Quick Verdict of the Synology DS423+ NAS – What We Said in the DS423+ Review in March 2023:
There are two ways we need to look at the Synology DS423+ NAS. In one way, the Synology DS423+ DOES support all of the features and services that users demanded in a fully-featured home/prosumer solution. It features an Intel Quad Core processor with embedded graphics, DDR4 memory, multiple gigabit ports, wide HDD/SSD compatibility and m.2 NVMe SSD support. These are all things popular and most certainly what users would want/expect in a fully featured home/prosumer solution (aka SOHO). Then, when you roll in DSM 7 and it’s enormous range of software and services, the DS423+ is an excellent NAS solution that counters a broad range of criticisms that were leveled at the DS923+ at launch. However, there is, of course, the unavoidable way that most long-term Synology users and those looking to upgrade an existing 2016/2018 Diskstation are going to look at the DS423+ – a Synology DS920+ with less memory and no expandability! For those that skipped the DSx20+ generation, the DS423+ is going to feel decidedly underwhelming at best and hugely disappointing at worst! Synology has made no bones that they prioritize their software and services, with hardware being an important but nevertheless secondary concern. The main criticism is that CPU being the same processor used in the 3 years previous generation. Intel has moved production away from the J4125 themselves several times (with most other NAS brands using the N5105 or J6412 right now) and although Synology has been known to move CPU architecture down through the generations previously, this is a particularly egregious example. If they had just scaled something up on this device, such as the network ports from 1GbE to 2.5GbE, add the option of a 10GbE upgrade or more over upgrade the base level memory from 2GB or 4GB. The Synology DS423+ IS a good NAS system and serves as a great means to enjoy the wide-ranging features of DSM privately or professionally! It just feels like more of a stop-gap system in some places and one that existing DS920+ or DS420+ owners will skip.
Read the Rest of the Review HERE. Alternatively, you can find out the Pros and Cons below, as a few retailers that sell the Synology DS423+ NAS. Thanks for reading and if you need any further help choosing the right NAS for your Plex Media Server, use the free advice section linked below. Have a great week.
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