Corsair Neutron XTi 480GB SSD Review

Corsair Neutron XTi 480GB SSD Review

Power requirements and efficiency

Storage device manufacturers by law must
provide power consumption specifications with their storage device products.
Quite often these specifications are quite vague, and rarely, if ever, publish
the power efficiency of their storage devices with regard to how much work a
storage device can do for a given amount of energy consumed. In this article we
will disclose with unprecedented precision, the energy efficiency of some
popular storage devices. 

Myce has now secured a piece of ‘state of
the art’ test equipment, which takes a sample every four micro-seconds, that I will
be using to measure the power consumption of consumer grade SSDs and HDDs. I’m so
very proud to be able to announce that Myce.com, in partnership with Quarch Technology, now aims to bring our
readers the most comprehensive, and accurate, power consumption tests ever
carried out on consumer grade storage devices, to be found anywhere on the
Internet.

Myce’s Power Testing will be carried out using
Quarch Technology products. More specifically we are privileged that Quarch has
allowed us to use their latest Programmable Power Module (‘PPM’) and we would
also like to take this opportunity to give a huge ‘thank you’ to Quarch for
providing this equipment. The PPM is specifically designed for testing low
power sleep states on modern SSDs and as such has a remarkably accurate low
level current measurement, down to 100
μA (micro amps,
or millionths of an amp). Please click here
for details.

Quarch Technology is a world leader in the
supply of testing solutions for the data storage industry and if you would like
any further information please visit their website by clicking here

Let’s take a closer look at the Quarch PPM
box in a bit more detail.

Corsair Neutron XTi 480GB SSD Review

Quarch
Technology PPM

The Quarch Technology PPM is able to
provide two power supply rails to the target SSD. A 12V (volt) rail is required
for PCIe based SSDs, and also for SATA HDDs, SATA HDDs also require the 5V rail
to function. All the power requirements of a SATA SSD are handled by the 5V
rail.

The Quarch Technology PPM can switch
between 5V and 3.3V on the secondary power output channel as required. So for
SATA based SSDs it is set to 5V, and for PCIe based SSDs, it is set to 3.3V.  

On the right of the Quarch PPM, you can see
the socket where the main power injection lead connects.

On the rear of the box (not shown) you will
find a USB 2 socket, a power socket (to supply power to the unit) and a
Torridon connection interface, for connecting to external equipment.

My setup.

Although the Quarch Technology PPM can be
used on a single PC, which can act both as host and measurement system, I will
be using two PCs to run the tests. One PC will handle the measurements, and the
second PC will act both as a host for the target SSD, and will also be used to
load the target SSD with data. This will allow me to do some pretty fancy power
consumption tests.

 


I will first show the type of workload
being used to load the SSD during the power consumption test. I will then
present the power consumption graph, and power consumption statistics of the
SSD.

I will display the results in the form of
bar graphs, at the end of each test carried out in this article, so one can
compare the results obtained on all the SSDs featured in this article.

I will use the following IOMeter test
patterns to load the SSD or HDD.

  • 4K random read and write at a queue depth
    of 1 (to emulate a lightweight consumer workload).
  • 4K random read and write at a queue depth
    of 4 (to emulate a medium workload).
  • 4K random read and write at a queue depth
    of 32 (to emulate a heavy workload).
  • 512K sequential read (to emulate reading
    a sequential file from the storage device).
  • 512K sequential write (to emulate writing
    a sequential file to the storage device).

Power requirements for a lightweight consumer workload. –
4K random read and write QD1

A typical lightweight consumer workload
will generally be at very low queue depths. Typically at a queue depth of one
or less. I’m testing random data at a block size of 4 Kilobytes, as this block
size of small random files is generally accepted as the most frequently
occurring in the consumer environment.

I will show the chart generated by the
Quarch PPM for the drive that I have tested. I will then show the results in
the form of bar graphs, so one can easily compare with other recently tested
SSDs.

There will actually be two bar graphs for
each test. The first graph will show the average power consumption during the
test run. The second graph, which is much more important, will indicate the
power efficiency of the storage device, showing how much work the storage
device can do for each Watt of energy it consumes.

4K Random Read – queue depth 1

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – 4K random read QD1

Corsair Neutron XTi 480GB SSD Review

We can see that the Corsair Neutron XTi
requires a lot of power.

Corsair Neutron XTi 480GB SSD Review

That extra power that is needed has an
impact on the IOPS per WATT score.

 

4K Random Write – queue depth 1

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – 4K random write QD1

Corsair Neutron XTi 480GB SSD Review

Also in the write test the Corsair Neutron XTi
is on the upper scale of the chart.

Corsair Neutron XTi 480GB SSD Review

The result is good.


Power requirements for a medium weight consumer workload.
– 4K random read and write QD4

A typical medium weight consumer workload
will generally be at a queue depth of four or lower. This workload would
typically involve some multitasking, with perhaps two or three applications
running, and processing data simultaneously.  I’m testing random data at a
block size of 4 Kilobytes, as this block size of small random files is
generally accepted as the most frequently occurring in the consumer
environment.

I will show the charts generated by the
Quarch PPM, for the drive that I have tested. I will then show the results in
the form of bar graphs, so one can easily compare with other recently tested SSDs.

4K Random Read – queue depth 4

Corsair Neutron XTi 480GB SSD Review

Corsair Neutron XTi 480GB – 4K random read QD4

Corsair Neutron XTi 480GB SSD Review

Again the result is not what I expected
from this SSD.

Corsair Neutron XTi 480GB SSD Review

As expected the higher power consumption
impacts the IOPS per WATT performance.

4K Random Write – queue depth 4

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – 4K random write QD4

Corsair Neutron XTi 480GB SSD Review

The Corsair Neutron XTi SSD is amongst the drives
that require a lot of power.

Corsair Neutron XTi 480GB SSD Review

Nothing has changed, the extra power that
the drive draws limits its overall performance in this test.


Power requirements for a heavyweight consumer workload. –
4K random read and write QD32

Whilst this workload is unlikely arise for
the casual consumer PC user, it could well appear in a semi-professional
consumer environment, such as in a graphics workstation. This workload would
usually involve heavy multitasking, and having several processes running
concurrently that require constant access to small files located on the storage
device for input or output.

I’m testing random data at a block size of
4 Kilobytes, as this block size of small random files is generally accepted as
the most frequently occurring in the consumer environment.

I will show the chart generated by the
Quarch PPM, for the drive that I have tested. I will then show the results in
the form of bar graphs, so one can easily compare with other recently tested
SSDs.

4K Random Read – queue depth 32

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – 4K random read QD32

Corsair Neutron XTi 480GB SSD Review

Nothing has changed, and for higher queue
depths the drive still needs more power.

Corsair Neutron XTi 480GB SSD Review

Once again the IOPS per WATT result puts
the Corsair Neutron XTi closer to the bottom of the chart.

4K Random Write – queue depth 32

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – 4K random write QD32

Corsair Neutron XTi 480GB SSD Review

Again the result is not that good for the
Neutron XTi.

Corsair Neutron XTi 480GB SSD Review

This time the Neutron XTi is much closer to
the middle of the chart but I would still have hoped for a better result.


Power requirements of a storage device when reading and
writing sequential data

Not all of a consumer workload is based
around the reading and writing of small random files. Many files are sequential
in nature, and can vary in size from a few Kilobytes to several Gigabytes, so
your storage device will spend a lot of time reading and writing sequential
data.

I’m testing sequential data at a block size
of 512 Kilobytes.

512KB Sequential read

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – Sequential read

Corsair Neutron XTi 480GB SSD Review

This result is very good for the Corsair
Neutron XTi SSD.

Corsair Neutron XTi 480GB SSD Review

Unfortunately this doesn’t translate that
well for the IOPS per WATT chart.

512KB Sequential write

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – Sequential write

Corsair Neutron XTi 480GB SSD Review

Again the Corsair Neutron XTi is showing
that it needs a lot power to complete this test.

Corsair Neutron XTi 480GB SSD Review

This time the result is very good.


Power requirements of storage devices when they are idle
and doing no work at all

The practical reality relating to power
consumption is that it can be quite erratic and sometimes unpredictable. Some
of us will invest in the most powerful PC we can afford, only to find that the
PC can spend quite a lot of time running and doing absolutely nothing. Storage
devices are no different.

Often we can be sitting idly pondering what
to do next, or perhaps browsing the Internet. When we arrive at a page that
interests us, we will read it, and that can take a fair amount of time to
complete. During this period the storage device will most likely be idle, but
still consuming energy.

In this test, I’m measuring how much energy
the storage device consumes when doing no work at all and with link power
management disabled.

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – Drive idle

Corsair Neutron XTi 480GB SSD Review

With all power saving features disabled the
Corsair Neutron XTi gives an outstanding result.


I will now show one more test, and this
should be regarded as for information purposes only.

Power requirement trace of an SSD booting Windows 10, in
real time.

This test is for interest only, and shows
the power requirements of the review SSD booting Windows 10 to the desktop.

Corsair Neutron XTi 480GB SSD Review

Corsair
Neutron XTi 480GB – Real time trace of the drive booting Windows 10 to the
desktop.

Corsair Neutron XTi 480GB SSD Review

Here is the result for the Corsair Neutron
XTi SSD.

Summary

It is clear that the Corsair Neutron XTi
SSD requires some extra power to deliver the high performance, and for most desktop
users this probably won’t be a problem. To be honest most power users will want
the extra performance and won’t care about the extra power consumption. The
drive also gave an impressive result when it was idle, so maybe there is room
for improvement with a future firmware? I hope so.

 

Now let’s head to the next page where we
will look at how the Corsair Neutron XTi SSD performs using Anvil’s Storage
utilities….