Nesteq ASM Xzero 500W Power Supply
Power supplies are often regarded as being fairly mundane and boring and simply the “work horse”
of most PC rigs. However, the Xzero unit that we have here today from Nesteq sees a range of new
and innovative technology that aims to bring the humble power supply into the modern era where
gizmos and gadgets seem to rank highly.
Advanced Silent Mode and a patented cable system are to name but a few of the features found on
the Xzero range but will this emphasis on new technology lead to its downfall in the core
performance of its rail stability and efficiency? Let’s take a look...
Highly efficient heat pipe cooling
Active PFC (Power Factor Correction)
Up to 89% Efficiency
ATX12V Version 2.2
EPS12V Version 2.91
BTX Version 1.0a
+12V Power - Plus Technology
Advanced Silent Mode Technology
Stack Effect Cooling Solution (SECS)
Power Monitoring Panel
Enhanced Easy Connecting System
Over Power / Voltage / Current / Temperature protection
Short Circuit Protection
Contents & Packaging
The retail packaging looks nice enough with a large picture of the Xzero unit along with a few close
ups on the capacitors and heatpipes. Nesteq actually make a very bold claim regarding the noise
levels too saying that it is “noiseless” at 0dBA. A few logos are highlighted at the top included the
ASM technology and +12C power plus connection.
Moreover, the front opens out revealing a window showing the unit inside along with a whole load
of technical jargon detailing the ASM (Advanced Silent Mode) and the cabling.
The back has even more details on this technology included some German translations and another
diagram showing the golden dial complete with the lights.
An output table is present showing all the rails, inputs and outputs for all the different models which
are in increments of 100 Watts from 400 to 700. Today, we are looking at the 500W version.
The numerous accessories arrived bundled inside what looks like a pencil case along with a manual.
The contents of the pencil case include the obvious suspects such as 4 screws and a power cord but
also a few others:
10 * Cable ties
PS-On ATX adaptor
4 * Plug Covers
The PS-on adapter is actually a very useful inclusion as it allows the unit to be powered on without a
motherboard. The only previous way to do this was to bend a piece of wire from a black connection
to a green one and then turn on the power; this is effectively what is inside the adapter too, just a
small piece of wire, but it takes it much easier to do.
Nesteq ASM Xzero
With the Nesteq Xzero range seemingly marketed mainly around with the ASM technology, it’s
seems like the obvious place to start. The dial, located just below the power socket, allows the
adjustment between Advanced Silent Mode and manual usage – simply push the dial in to select the
former and an LED will light up to show that this is the case.
With ASM selected, the fan is redundant until the temperature hits 65 degrees when it fires up to
reduce to the temperatures to a safe level (obviously Nesteq have calculated this to be 65 degrees or
For manual settings, the dial can just be turned to adjust the fan speed according the users
preference; this is something new that I have not seen implemented into power supplies before and
should be of great significance to silent enthusiasts.
A series of LEDs sit just above the dial too for the different rails: +3.3V, +12V, +5Vsb and +5V. When
working properly each has a green light but if a rail should fail in any way, the light will turn off.
Whilst in principle this sounds quite useful, I doubt many users will actually check the back of their
units very often to check.
On a less technical note, the Xzero unit looks really sleek with its matte black coating and shiny gold
grill and dial. One side I dedicated solely to an Xzero logo with a hexagonal background that, besides
doing anything else, adds some style.
Flipping the unit over, reveals its underbelly or in this instance the outputs table. There’s nothing too
startling here with a total of four +12V rails each at 20A. The +5V rail has the same maximum current
output with the +3.3V a little higher at 24A. In total a max power output of 500W is achieved.
Nesteq’s patented “+12V Power plus Connection” provides a power boost for the PCI-express and
EPS connections; effectively the current is increased to 30A to achieve the boost.
With the majority of the cabling being modular, a number of ports occupy the front of the Xzero
units. A small sticker distinguishes which connector is intended with use with which cable and in
total there are 4 for PCI-e and 4 for FDD/SATA/molex cables.
A small vent lies underneath the connections to in order to aid the passive cooling and the stack
cooling solution. The fan actually faces upwards too and draws cold air up through the heatsinks in
order to achieve a more efficient passive cooling method. Of course the fan is still required to kick in
once the temperature rises too high.
Cables & Connectors
Of the cables that are not modular, the 20+4 ATX motherboard and 4 and 8-pin EPS connectors are
obvious choices but there is also a small fan header which connects into the motherboard in order to
monitor the fan speeds. Using ASM mode this isn’t overly useful but it certainly becomes more
prevalent with manual control of the fan.
All of the cables feature black sleeving which a plastic end holding it in place; this not only looks
tidier but also prevents the excessive number f individual cables from being an issue.
Two bundles of modular connections come with the Xzero 500W unit: one with the PCI-e cables and
one with the FDD, molex and SATA connectors.
Here is the full list of cables:
2 x PCI-Express
2 x SATA
2 x Molex
2 x FDD
1 x 390mm Extension cable
1 x 5V fan connection cable
1 x 12V fan connection cable
N.B. The SATA, molex and fan connection cables all contain three connections.
The fan connection cables are a very useful inclusion as, for users with multiple system fans and with
limited fan headers on the motherboard; they can be plugged straight into these connections
instead of purchasing a molex adapter. The choice of both 5V and 12V is also very useful.
Overall, Nesteq’s connecting system is first rate allowing great flexibility and versatility for increasing
cable length and combing different cables together.
Testing power supplies is a bit of a mine field, as many sites - like our own - test rail voltages to
measure stability and tightness to the ideal rail rating. For a multitude of reasons these are
imperfect tests. That said, without several tens of thousands of pounds worth of equipment, it's not
possible to accurately measure PSU ratings.
With that in mind, we still use our multimeter rail test during idle and load states to give something;
if at least a real world comparison between units. It's not perfect, and we would ask our readers to
not base your PSU purchase solely on this review, but hopefully we can give some measure of
comparing units. If not, then at least you know these units are capable of running out test setup for
a prolonged period of time; or not.
The software used to load the PC was Prime95 (Large FFTs), and the 3Dmark benchmark running at
full tilt to load the GPU.
Idle (approx. 200W)
3.3V 5V 12V
Antec CP-850 3.35 5.15 12.20
NOX Apex 700W 3.34 5.19 12.11
Seventeam V-Force 3.37 5.18 12.17
Cooler Master Silent 3.36 5.20 12.18
Pro M 500W
Nesteq ASM Xzero 3.37 5.13 12.18
3Dmark Vantage (approx. 280W)
3.3V 5V 12V
Antec CP-850 3.36 5.14 12.14
NOX Apex 700W 3.38 5.17 12.08
Seventeam V-Force 3.37 5.14 12.10
Cooler Master Silent 3.40 5.18 12.11
Pro M 500W
Nesteq ASM Xzero 3.38 5.14 12.18
Prime95 (approx. 370W)
3.3V 5V 12V
Antec CP-850 3.33 5.13 12.18
NOX Apex 700W 3.33 5.14 12.14
Seventeam V-Force 3.35 5.19 12.23
Cooler Master Silent 3.33 5.16 12.20
Pro M 500W
Nesteq ASM Xzero 3.36 5.18 12.22
Prime95 + 3Dmark Vantage (approx. 450W)
3.3V 5V 12V
Antec CP-850 3.34 5.16 12.08
NOX Apex 700W 3.37 5.14 12.09
Seventeam V-Force 3.38 5.18 12.08
Cooler Master Silent 3.39 5.22 12.23
Pro M 500W
Nesteq ASM Xzero 3.41 5.24 12.15
Looking at the results on the whole, we must first point out that all the results are well within ATX
specifications and most are very close to the stated rail voltage.
Compared to the other units, most of which have a high max power output, the readings are not
quite as tight as say the CP-850. The 5V rail particularly was always over 0.1V out; not a great deal it
may seem but if we are nit-picking it could be a little tighter.
Power Consumption & PF rating
PF Standby PF Idle PF Load Watt Watt Idle Watt
Antec CP-850 0.87 0.89 0.98 4 201 445
NOX Apex 700W 0.86 0.94 0.97 2 206 434
Seventeam V-Force 0.88 0.93 0.96 5 211 428
Cooler Master Silent 0.87 0.94 0.99 3 200 437
Pro M 500W
Nesteq ASM Xzero 0.87 0.94 0.97 5 203 430
N.B. Load achieved here using Prime95 + 3Dmark Vantage.
In regards to efficiency, the results are about average and there’s not really much to say. It’s not
going to wow you with very high efficiency but then neither is it going to shoot up your electricity
The ASM mode does live up to its claim in being totally silent, well it would have been hard not too
with the fan not spinning. However, when the fan does kick in at 65 degrees, it does churn out a fair
bit of noise and this may, in part, be due to the older sleeve bearing which does produce a few
But, on the whole the ASM mode is very impressive indeed and much better than conventional PSUs
which have fans spinning at all times.
At a pinch over £100, this unit is not exactly cheap for a 500W unit but from what we’ve seen it’s of
very high quality.
The new technology found in the Xzero series is very encouraging and it’s great to see Nesteq trying
and implementing new ideas and concepts into their products.
For me, the ASM mode is a triumph and although the fan could be considered a little noisy when it
does kick in, the fact that it only does at 65 degrees it worth it. The versatility of being able to
manually set the fan speed again demonstrates the attention to detail put into this design.
However, this is not the only exciting feature. The LEDs that turn off to notify a power failure and the
power bower for the PCI-e connectors are yet more reasons to part with over £100 to own one of
Sure not all of the technology is really needed; for instance I doubt many users will really check to
see if the green lights are on and the rail stability wasn’t the best we’ve seen although we can’t be
too quick to criticise here as our test methods aren’t exactly prefect.
To sum it up, the Xzero 500W unit has an array of technology and extras that set it apart from the
crowd and make it well worth a look but for £100, it’s going to be hard to make customers part with
Reasonably rail stability
Competitive efficiency ratings
Cable connecting system
Not all the technology really required