January 16, 2019
HGST ULTRASTAR HE12 vs Seagate Exos

HGST ULTRASTAR HE12 vs Seagate Exos Hard Disk Spec Comparison

Seagate and Western Digital are two of the most successful computer storage providers. They manufacture various types of storage solutions including mainstream hard disks, SSDs, network storage, storage for CCTV / Security system, etc. Today, we will be talking about conventional enterprise level hard drives, and figure out which of them provides the best solution (HGST ULTRASTAR HE12 vs Seagate Exos).

For this comparison, we have selected following products from both Seagate and western digital:

HGST ULTRASTAR HE12 vs Seagate Exos

We will go through every small technical detail and specifications, which will help us understand what and how something makes one better from the other. Note that both of these products are enterprise level storage solutions and we have opted same storage capacity models so that the comparison would be fair and square.

So without any more delay, here is our comparison:


Specification HGST Ultra-Star HE12

Seagate EXOS X12

Device Type Hard drive – internal Hard drive – internal
Bytes per Sector 512 512
Interface SATA 6Gb/s SATA 6Gb/s
Buffer Size 256 MB 256 MB
Weight 23.28 oz 22.93 oz
Manufacturer Western Digital Corp. Seagate Technology

Let’s begin with a general introduction to both products. As you may already know, EXOX X12 is manufactured by Seagate storage solutions while HGST Ultrastar HE12 is a western digital product. Both models used in this comparison deliver 12 GB of storage capacity and thus having the same amount of buffer size, which is 256 MB.

The buffer cache merely is embedded memory on a standard hard disk drive which helps it to buffer data between the storage drive and rest of the computer system. The buffer cache, the faster a hard disk drive will perform. 256 MB is maximum buffer cache for modern hard disk drives; you cannot get better than that. Here, you should note SSDs hold up to 1 GB of the buffer, that’s why they perform comparatively faster.

Both Ultrastar HE12 and EXOS X12 feature SATA interface, with up to 6 GB/s transfer rate support. You might have noticed that Seagate is a bit lighter than HGST. However, it matters the least or not at all.


Specification HGST Ultra-Star HE12

Seagate EXOS X12

MTBF 2500000 sec 2500000 sec

MTBF stands for Mean Time Between Failure. This unit is used to scale the reliability and durability of a storage device. It indicates the average time between one inherent failure/error and the next one during device’s lifespan. Here, you can see that both storage drives have the same MTBF. However, these numbers are unreliable and unrealistic sometimes.

Interface Provide

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Qty 1 1
Storage Interface Serial ATA-600 Serial ATA-600

Hard Drive

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Form Factor 3.5″ 3.5″
Spindle Speed 7200 rpm 7200 rpm
Features: 24×7 availability, Enterprise, Instant Secure Erase (ISE), Perpendicular Magnetic Recording (PMR) 24×7 availability, Advanced Write Caching, Seagate Secure, Super Parity, Superior Wide-Weld Hermetically Sealed-Drive enclosure, advanced format 512e, pressure sensor, Helium technology, Hot-Plug Support, Low Halogen, Multi-Step Forged Helium Sealed-Drive design, Organic Solderability Preservative, Power Balance technology, PowerChoice, Seagate RAID Rebuild
Hard Drive Type internal hard drive internal hard drive
Form Factor (Short) 3.5″ 3.5″
Form Factor (metric) 8.9 cm 8.9 cm
Form Factor (Short) (metric) 8.9 cm 8.9 cm
Storage Interface Serial ATA-600 Serial ATA-600
Interface Serial ATA-600 Serial ATA-600
Average Seek Time 8 ms 4.16 ms
Data Transfer Rate 600 MBps 600 MBps
Buffer Size 256 MB 256 MB
Bytes per Sector 512 Hz 512 Hz
Non-Recoverable Errors 1 per 10^15 1 per 10^15

Both HGST Ultrastar HE12 and Seagate EXOS X12 support standard 3.5″ bays and deliver spindle speed of 7200 RPM. Both deliver same data transfer rate of 600 MB/s.

Moreover, their bytes per sector, buffer size, and nonrecoverable error values are same as well. The non-recoverable error indicates the occurrence of an error which cannot be recovered later on. The only difference here is of average seek time. HGST has a seek time of 8 milliseconds, for Seagate, it is only 4.16 milliseconds. This difference seems tiny but makes the significant impact on real-time performance. The less seek time; the faster data will be loaded into main system memory.

If you put it in figures, Seagate delivers almost double speed in seek time, compare to HGST, so its clear winner here. Moreover, it throws many additional security and performance features while HGST offers a few only.

Environmental Parameters

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Min Operating Temperature 41 °F 41 °F
Max Operating Temperature 140 °F 140 °F

There is zero difference in minimum and maximum operating temperature range for both HGST Ultrastar HE12 and Seagate EXOX X12.

Dimensions & Weight

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Width 4 in 4 in
Depth 5.8 in 5.8 in
Height 1 in 1 in
Weight 23.28 oz 22.93 oz

As both HGST Ultrastar HE12 and Seagate EXOS X12 possess same form factor, their dimensional factors are exactly same. However, there is a slight difference in the weight, which is the novice. We are pretty sure it won’t affect the build at all.

Power Consumption

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Mode active, idle active, idle
Value 5.3 Watt, 7.2 Watt 5 Watt, 7.8 Watt

Both the models have two states only, active and idle. It is quite surprising they are not offering sleep mode. Without it, the device will stay in the idle situation rather than turning itself off while your system is hibernating. In the active state, HGST Ultrastar HE12 consumes 0.3 Watts more than Seagate EXOS X12.

However, in the idle state, Seagate EXOS X12 consumes 0.6 Watts more compared to HGST Ultrastar HE12. HGST consumes a bit less power compared to Seagate. However, it is quite considerable since Seagate is offering more features and reduces average seek time.

Service & Support Details

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Type limited warranty limited warranty
Full Contract Period 5 years 5 years

Shock & Vibration Tolerance

Specification HGST Ultra-Star HE12

Seagate EXOS X12

Shock Acceleration (Operating) 70 g
Shock Duration (Operating) 2 ms half sine wave
Shock Acceleration (Non-operating) 300 g
Shock Duration (Non-operating) 2 ms half sine wave
Vibration Acceleration (Operating) 0.67 g
Vibration Frequency Range (Operating) 5-500 Hz
Vibration Acceleration (Non-operating) 1.04 g 2.27 g
Vibration Frequency Range (Non-operating) 2-200 Hz 10-500 Hz

As described above, both manufacturer’s are offering five years of limited warranty on these products, which is great and assuring. For more details on their warranty policies, you can visit the links below or refer to manufacturer’s website and search for the particular product.

As the table above indicates, HGST offers much more features when it comes to shock and vibration tolerance. Here, it knocks out the Seagate completely. When building a full-fledged rig, there are high chances of vibrations and shocks on peak moments. These factors would surely make a difference in such conditions.

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In the end, all we can say is that Seagate is better when it comes to faster data access and security features. However, HGST offers more durability and sturdiness.

It is up to you what you require more. We hope this post helped you to understand fundamental differences between these two products so that you can choose the right one for yourself.

Use the comment box below for any queries or suggestions, Thank You!

Disclosure: We are a professional review website that sometimes receive compensation or free units from the companies whose products we review. We test each product thoroughly and give high marks to only the very best. We are independently owned and the opinions expressed here are our own.