Western Digital PR4100 vs EX4100

These devices are a good choice for building a private network for your home office or small business collaborations. Their 4-disk capacity provides a good storage volume and various My Cloud apps offer lag-free multimedia streaming.

Starting with similarities of both devices:

  • Both devices are designed identically and also specify the same physical dimensions.
  • Both NAS shows a similar cloud interface.
  • Both tools provide equal sharing and backup options.
  • Warranty duration is also the same for these NAS.

Where the WD PR4100:

  • Is equipped with a comparatively efficient processing unit.
  • Carries larger internal storage chip.
  • Presents faster read and write responses in comparison.
  • Supports the latest operating systems.

WD PR4100, a member of MyCloud Pro series, presents a similar outlook but takes the edge over its competitor due to relatively improved temperature endurance.

Plus, this device provides faster data transfers by processing a huge amount of data very quickly. Vast internal memory further adds to the processing efficiency of this gadget.

And the WD EX4100:

  • Provides private cloud storage at a relatively lower price.

WD EX4100 comes from the My Cloud Expert series; it is a sleek black cloud device that allows you to store data on installed hard disks, and USB drives.

It is a proficient device for local networking as two RJ45 GbE ports provide failover support and link aggregation.

Compared to EX4100, My Cloud PR4100 operate with a quad-core processor, has larger integrated memory, shows faster read-write responses, functions in a wide temperature range, and supports relatively newer OS versions. However, both devices rank the same for cloud storage, sharing, and backup efficiency.

Let’s compare these NAS Devices:

Number of bays44
Drives pre-configuredYesYes
Compatible DrivesFour x 3.5-inch hard disk drivesFour x 3.5-inch hard disk drives
Ports2 x Gigabit Ethernet RJ-45 ports   3 x USB 3.0 ports  2 x Gigabit Ethernet RJ-45 ports   2 x USB 3.0 ports   1 x USB 2.0 port  
RAID ModesSpan, JBOD, RAID 10, 5, 1, 0Span, JBOD, RAID 10, 5, 1, 0
EncryptionAES encryption (256 bit)AES encryption (256 bit)

Processor and RAM

PR4100 carries more efficient processing and memory units.

It is equipped with an Intel Pentium N3170 quad-processor.

Hence, its CPU has the ability to run more processing threads at the same time.

Though both devices work at the processing frequency of 1.6 GHz, the frequency of this device may burst up to 2.56 GHz making it more efficient than the competitor.

Plus, its inbuilt memory chip has double the capacity of its contestant.

Conversely, Western Digital My Cloud EX4100 carries Marvell ARMADA 388 dual-core processor which has reduced efficiency in comparison.

Moreover, its integrated memory is also smaller than the competitor.

ProcessorIntel Pentium N3170, Quad-coreMarvell ARMADA 388 dual-core
Processing frequency1.6 to 2.56 GHz1.6 GHz
Installed storage4 GB DDR3L2 GB DDR3


WD PR4100 works at a higher speed than its competitor due to its relatively efficient CPU and RAM.

As its processor is high core and installed memory is larger, it has the proficiency to perform read-write operations at a faster pace.

Conversely, the reading and encoding speed of Western Digital EX4100 is lesser in comparison.

Its processor and RAM are half as efficient as the competitor due to which it presents slower read-write responses.

Reading speed118 MB/s114 MB/s
Writing speed114 MB/s108 MB/s


These storage systems present an identical outlook as both are glossy black, tower-form four-bay devices.

Their drive bays are hot-swappable and tray-less and have a mesh-like design on the drive handles.

Along with that, the front side carries a USB 3.2 Gen 1 port and copy USB button, power and scroll buttons, drive LEDs to indicate drive status, and an LCD screen.

The rear portion contains a fan exhaust, two Ethernet ports, two USB ports, DC power inlets, a Kensington security slot, and the reset button.

Comparatively speaking, both devices only differ from each other for USB interface. PR4100 takes the win here as all three of its USB ports are generation 1 (USB 3.0).

Besides that, this device shows better performance in extreme temperature conditions.

It can be used at relatively colder temperatures and can be stored within a wide temperature.

Conversely, WD EX4100 has two USB 3.0 ports (one on the front and one on the backside) while the third port is a USB 2.0.

Plus, this device can be stored and operated in a smaller temperature range.

Color SchemeBlackBlack
Height (inches)9.139.13
Width (inches)6.696.69
Depth (inches)7.567.56
Operational temperature32 to 95°F41 to 95°F
Storage Temperature-40 to 158°F-4 to 149°F

Available models and space variants

Both these devices are 4-bay network attached systems but they have different space variants. PR4100 comes with more space variants than its competitor.

It is available in the pre-configured variants of 72TB, 64TB, 56TB, 40 TB, 32TB, 24TB, 16TB and 8TB. Plus, you can also buy a diskless enclosure.

In contrast, EX4100 has fewer space variants with the highest capacity of 56TB.

Space variants72TB, 64 TB, 56 TB, 40 TB, 32 TB, 24 TB, 16 TB, 8 TB, 0TB (enclosure only)56 TB, 40 TB, 32 TB, 24 TB, 16 TB, 8 TB, 0TB (enclosure only)

Cloud storage interface

Both devices utilize the MyCloud service to build a cloud space, enabling the users to store, sync, and share across their private network. Users can easily access NAS from far-off places when “remote access” is enabled.

Through WD Sync app, these systems automatically synchronize remote database with NAS data when connected to internet.

Plus, mutual synchronization with public cloud services is enabled in both these systems.

You can share, receive and synchronize data from other My Cloud devices as well as from Amazon S3 and ElephantDrive accounts.

Supported OS and browsers

Both tools support macOS and Windows but Pro operates with relatively latest versions.

It is compatible with Windows 7, 8, 8.1, 10 and macOS 10.8 to 10.11. 

For web browsing, it works with Google Chrome, Firefox, Safari, and Internet Explorer.

For multimedia management, it supports devices that enable streaming applications like DLNA/UPnP or Plex.

Conversely, Expert works with relatively older versions of OS, showing compatibly up to Windows 8.1 only.

It is compatible with the same streaming applications and supports the same web browsers.

Sharing and Backup

These systems provide efficient networking services as users associated with the NAS can not only access the stored data but are also able to upload files to the database remotely.

Plus, exclusive groups and quotas are enabled by both systems to make collaboration hassle-free.

To access NAS files, users can use the WDMyCloud app and other multimedia apps from Western Digital.

Likewise, you can share your files across two popular commercial clouds (Elephant Drive and Amazon S3).

Similarly, both PR4100 and EX4100 rank at the same position for backup abilities.

They offer efficient local backup by enabling various RAID levels (JBOD, Span, RAID 10, 5, 1, 0) with up to two disk-fault tolerance.

Thus, if the data on one disk is accidentally lost, you can retrieve it as it has been mirrored on the adjacent disk.

Plus, remote backup service is available through the private cloud associated with the NAS as well as through Amazon S3 and ElephantDrive.

WD Smartware Pro is the automatic backup software for PC clients.

For mac users, these devices support Time Machine- the inbuilt backup software of Apple devices.


The setup procedure for these devices is identical and quite easy as well. Plus, you don’t have to configure it necessarily because you can choose from a wide range of pre-configured variants.

However, if you buy the diskless version or want to replace hard disks on your NAS, you can do that in a few minutes without any tools or screw opening as both devices have tray-less drive bays.

Follow these simple steps to install a storage disk;

  1. Pull the handle outwards to open a drive bay.
  2. Take a hard disk and slide it inside the drive bay. Make sure you put it in the right direction as indicated in the user manual.
  3. Push down the handle and press slightly to close the drive bay.
  4. Power up your network-attached system. Now, you can access MyCloud Dashboard to store and backup your data locally.
  5. For cloud storage and networking, provide an internet connection to configure cloud settings through the MyCloud online portal.


Western Digital has built these cloud devices with sturdy casing material, efficient chip integration, and an improved operating system.

That is why both devices provide optimized operations for many years.

The company gives a replacement warranty for up to 3 years on all pre-configured systems.

But if you opt for a diskless enclosure, the warranty is provided for a lesser duration as there are more chances of damage when beginner users rather than company experts configure the devices.

Still, you get a warranty for 2 years from the date of purchase.