Kingwin LZP-1000: Platinum Efficiency at a KiloWatt

The subject of our second KW power supply test in a row is an 80 Plus Platinum rated Kingwin vying for top honors among gaming silent PC enthusiasts. How does it fare against the Seasonic X1050 celebrated in a recent review?

Product	Kingwin Lazer Platinum 1000W (LZP-1000) ATX Power Supply
Sample Supplier	Kingwin Technology
Market Price	~US$230

Kingwin made quite an impact at SPCR last year with the >93% efficient Lazer Platinum 550W, which also turned out to be the quietest fan-cooled power supply at loads below 500W. This sample was followed by a 500W fanless version, which also boasted similarly excellent energy efficiency and almost complete freedom from electronic noise in actual operation. Both of those models are ideal for "classic" silent PC enthusiasts, who tend to favor minimalist PCs that draw less power and are easily cooled with a minimum of forced airflow. Now, Kingwin has released a 1000W model geared to more extravagant PC users, including gamers who favor multiple high power video cards and extremely overclocked CPUs. This is the top model in a series which includes three other models, at 650W, 750W and 850W.

The first generation of kilowatt PSUs that appeared around 2006 were massive, substantially longer and heavier than standard ATX12V models. They had to be, as the prevailing maximum efficiency was not much higher than 80%. At full rated power, the excess heat produced by a KW PSU was around 250W. Fast noisy fans and oversized heatsinks were required to deal with this heat. Hence the extra size and mass of those early mega-power PSUs.

Our recent review of the 80 Plus Gold rated Seasonic X1050 showed that KW PSUs have come a long ways since those early days. The new Seasonic not only achived >90% efficiency, it also challenged the acoustic performance of the quietest PSUs at <500W loads. The recorded SPL at 700W of 28 dBA@1m was many decibels lower than any other PSU we’ve tested.

The Kingwin Lazer Platinum 1000W looks to one-up the Seasonic X1050. It’s primary edge is efficiency — the official 80 Plus test report cites 92.64% efficiency at 500W load — compared to 90% required for 80 Plus Gold. We’ll see how its acoustics hold up.

PACKAGING & FEATURES

Big full color package for the Kingwin LZP-1000. Good packaging, including a soft pouch for the cables. Power supply, all the cables, and four thumbscrews to mount the PSU. The attached cables are sleeved, others are in the flat data-cable style. The flat profile can make cables easier to route in some cases. The 1.5m long AC cable looks sufficiently butch for the 1000W PSU power rating, with markings for 105ºC and 16/3C (16 gauge); such cables are usually good for 1625W or 13A at 125V.

Kingwin LZP-1000 FEATURE HIGHLIGHTS
FEATURE & BRIEF	Our comment
Compliance with ATX 12V v2.2, EPS 12V v2.91, and SSI EPS 12V v2.92 Specification	Good.
140MM Fan (25dBA) with Intelligent Speed Control and ECO Intelligent Thermal Control System (Patent)	A variation of the stepped thermal fan control pioneered by Seasonic years ago.
Crystal Cube Modular Plug w/ Patented Power Connector Cable Management – 8 connectors	Just looks like a different connector.
Hybrid Dual Voltage Automatic Switch System (Patent)	What does this mean?
Superior Vertical Double Layer Main Transformer (Patent)	OK… but superior to what?
More than 2,000 Times ON/OFF Test	OK.
80 PLUS® Platinum High Efficiency Power Supply Certified — 50% Load (92% Efficiency), 20% Load (90% Efficiency), 100% Load (89% Efficiency)	This is why we’re interested.
Stable + 12V Current	Single 12V rail?
Safety certifications: cTÜVus, TÜV, CB, CE, FCC, CCC, C-Tick, BSMI	As expected.
Over Power/Under Power/Over Voltage/Short Circuit Protections	OK.
Temperature Range: 0ºC ~ 50ºC	Excellent.
Full Range Design from 115V ~ 250V (Active PFC)	Like most high end PSUs on the retail market.
5 year warranty	Matches compeititors.
Physical: 180(L) x 150(W) x 86(H)mm, 6.5 lbs	30mm longer than normal.

VISUAL TOUR

Like other models in the LZW series, the 1000 is painted flat black, with a cosmetic decal on one side and specifications label on top. The sheet metal seems about average thickness, and the casing is about 3cm longer than normal. The honeycomb pattern exhaust grill is very open to airflow, and there are no other vents other than the 140mm fan intake. The overall impression is of a decent but not exceptional quality casing, with good quality parts inside.

The casing is fairly standard but a but longer than usual. Note the red ECO switch over the AC input connector. It switches the cooling profile from low noise to semi-passive or hybrid. In the latter mode, the fan does not start spinning until some internal sensor temperature reaches >45ºC. The same 8-pin connector is used for all the modular cable outputs. Despite the modular cables, there is quite a big bundle of attached output cables: The main ATX, two cables for PCIe card 12V, 8-pin AUX12V and 4/8-pin AUX12V. The spec label.

This time around, I’ve decided to forego the photos of the interior. From what can be seen through the fan vanes, it looks similar to the LZW-550, with smallish heatsinks and quality 105°C capacitors. I have little doubt that the fan is the same model as the one used in the LZ-550. In all honesty, my technical knowledge of PCB-level components is not extensive enough to add much value to the review. For such commentary, you’re better off visiting Johnnyguru.com; their reviews do feature interesting commentary on such details. I’m more interested in the end results, and with the possible exception of the fan, no longer much interested in the fine details inside. For most users, the PSU is a black box, and what matters most is how it performs.

OUTPUT CABLES

Fixed:

1 – ATX connector (58cm) 20+4 pin
2 – PCIe connector (58cm) 6/8-pin
1 – AUX12V connector (58cm) 4/8 pin
1 – AUX12V connector (58cm) 8 pin

Detachable:

3 – PCIe (53cm) 6/8-pin
1 – PCIe
6/8-pin extender (13cm)
3 – four SATA connectors (90cm)
1 – three 4-pin Molex connector (80cm)
1 – three 4-pin Molex connector + floppy drive connector (90cm)

TESTING

For a fuller understanding of ATX power supplies, please read
the reference article Power
Supply Fundamentals. Those who seek source materials
can find Intel’s various PSU design guides at Form
Factors.

SPCR’s
PSU Test Platform V4.1. is the basic setup for the testing. It is a close simulation of
a moderate airflow mid-tower PC optimized for low noise. There is one major change: The primary testing is done with the PSU NOT inside the hotbox but atop it, out of the heat path. This is in recognition of several realities that prevail today:

• In SPCR’s test platform, the internal temperature varied proportionately
  with output load. The tested PSU was subject to this heat, and operating ambient temperature rose with increased load, reaching >40°C and often much higher at full power. This was a realistic simulation of a mid-tower PC case where the PSU is mounted conventionally at the top back portion of the case.
• The vast majority of "serious" PC cases for the home builder place no longer position the PSU at the top back corner. They put the PSU at the bottom/back corner, mostly out of the path of heat from the other components in the case. This design concept took root with the Antec P180 going back over 5 years, and dominates the DIY case arena. This means the PSU generally has to dissipate only its own heat.

Some time in 2011, we reversed our thermal testing approach: The PSU is tested briefly in the hotbox only to check on what happens to noise, fan speed and temperatures when it is used in an outmoded case design that forces the PSU to draw air from inside the PC case. In this test, roughly 30~50% of the air heated up by the output of the PSU ends up being evacuated through the PSU.

Acoustic measurements are performed in our own anechoic chamber with ambient level of 11 dBA or lower, with a PC-based spectrum analyzer comprised of SpectraPLUS software with ACO Pacific microphone and M-Audio digital audio interfaces.

REAL SYSTEM POWER NEEDS: While we test the PSU to full
output in order to verify the manufacturer’s claims, real desktop PCs simply
do not require anywhere near this level of power. The most pertinent range of
DC output power is between about 40W and 300W, because it is the power range
where most systems will be working most of the time. It is true that very elaborate systems with the most power hungry dual
video cards today might draw as much as another 150~300W, but the total should
remain under 600W.

TEST RESULTS

The ambient temperature was 22~23°, and the ambient noise
level was ~10.5 dBA.

1. EFFICIENCY — This is a measure of AC-to-DC
conversion efficiency. The ATX12V Power Supply Design Guide recommends 80% efficiency
or better at all output power loads. 80% efficiency
means that to deliver 80W DC output, a PSU draws 100W AC input, and 20W is lost
as heat within the PSU. Higher efficiency is preferred for reduced energy consumption
and cooler operation. It allows reduced cooling airflow, which translates
to lower noise. The 80 Plus Platinum standard calls for 90% efficiency at 20% load, 92% efficiency at 50% of rated load, and 89% at full rated load.

At the super low 20W load, efficiency was considerably lower than the LZW-550. Efficiency
rose quickly as the load was increased, but remained lower than with the 550W model, and 90% efficiency was reached around
150W, compared to 65W on the smaller model. But as load increased further, the efficiency of the 1000W model reached similarly high levels, actually breaking 94% at 400W. >90% efficiency was maintainee to about 700W, when it began to decline. At full power, our sample missed the required 89% by 0.6%. I don’t consider this a significant breach of the specification, as the result is well within the accuracy range of SPCR’s load testing system. At such high power levels, I doubt the system has better than ±1.5% accuracy.

The lower efficiency at <150W is to be expected of a 1000W PSU, which is optimized for operation at higher loads. The 94.1% efficiency reached at 400W is the highest measured in any SPCR PSU test thus far. The Seasonic X1050 has somewhat better very low power efficiency, but beyond 100W load, the Kingwin stayed a couple percent higher to full load, which is as it should be. The one anomaly was at 700W load, where the difference between the two KW PSUs fell to just 1.1%.

2. VOLTAGE REGULATION refers to how stable the output voltages
are under various load conditions. The ATX12V Power Supply Design Guide calls
for the +12, +5V and +3.3V lines to be maintained within ±5%.

At all load levels, the critical 12V line was within 3%
of 12V. It started high, at 12.37V (+3%) and dropped with increased load to 11.76V (-2%) at full load. The 5V line started a touch high, too, at 5.16V, and went down to 4.89V at full load (+3.2% to -2.2%). 3.3V ranged from 3.39V to 3.32V (+2.7% to dead on). These are good results, not the best we’ve seen but substantially better than required by the ATX12V design guide.

3. AC RIPPLE refers to unwanted "noise"
artifacts in the DC output of a switching power supply. It’s usually very high
in frequency (in the order of 100s of kHz). The peak-to-peak value is measured.
The ATX12V Guide allows up to 120mV (peak-to-peak) of AC ripple on the +12V
line and 50mV on the +5V and +3.3V lines. Ripple on all the lines was excellent
at all power levels, generally staying under 15mV through the lower half of
the power range. Even at 1000W output, the 12V ripple stayed at just 35mV.
It’s virtually identical to the superb results of the Seasonic X1050 (and the smaller Kingwin LZP-550).

4. POWER FACTOR is ideal when it measures 1.0. In the most
practical sense, PF is a measure of how "difficult" it is for the
electric utility to deliver the AC power into your power supply. High PF reduces
the AC current draw, which reduces stress on the electric wiring in your home
(and elsewhere up the line). It also means you can do with a smaller, cheaper
UPS backup; they are priced according to their VA (volt-ampere) rating. Power
factor was very good for this model, running at or close to 1.0 through most
of the loads and no lower than 0.92 even at just 20W load.

5. LOW LOAD TESTING revealed no problems starting at very
low loads. Our sample had no issue starting up with no load, either, and the
power draw was low. The 0.4W power draw in standby (power
switch on but computer off) is excellent.

6. LOW & 240 VAC PERFORMANCE

The power supply was set to 700W load at various AC input
voltages. Most full-range input power supplies achieve higher efficiency with
higher AC input voltage. SPCR’s lab is equipped with a 240VAC line, which was
used to check power supply efficiency for the benefit of those who live in higher
mains voltage regions. We also used a hefty variac to check the stability of the PSU
under brownout conditions where the AC line voltage drops from the 120V norm.

Efficiency improved to over 96% at the higher voltage.
This is much higher than the minimum 94% required at 50% load by the 80 Plus Platinum standard for 230VAC operation, though admittedly, our 244V input is 6% higher than 230VAC. The sample passed the 100VAC minimum input without any issues.
Neither voltage regulation nor ripple changed appreciably during these tests.

7. TEMPERATURE, COOLING & NOISE

The LZW-1000 uses the same cooling system as the LZW-550. A notice in the product package cautions that the fan does not spin when the unit is first turned on. The following illustration explains its function:

Note that a red switch above the AC input connector on the back panel allows you to switch between ECO Intelligent and "Normal" thermal control. It is in the ECO Intelligent position that the fan does not spin up at turn-on. In position #1, the fan does indeed turn on even with super low load, although its speed does not change until ~500W load is reached.

In ECO mode, it is a "semi-passive" cooling system and the fan comes on only when high temperature is reached. The illustration above states that the turn-on temperature is 65~70°C, and and the fan will stop spinning when the temperature drops to 45~50°C. It is not clear just where in the PSU this temperature is monitored.

Kingwin LZP-1000: Power vs Noise
Load (W)	SPL (dBA@1m)	Exhaust
22.2	17 / 0	23
41.9	17 / 0	24
65.5	17 / 0	30 / 25
90.7	17 / 0	33 / 26
149.0	17 / 0	33 / 26
199.6	17 / 0	35 / 28
251.2	17 / 0	35 / 28
300.3	17 / 0	36 / 29
400.9	17 / 0	37 / 29
500.5	20	41 / 30
699.9	23	49 / 31
1001.2	25	54 / 33

This is why two SPL numbers are shown in the above table: When set to ECO mode, the fan did not turn on until 500W load, but when set to normal, the fan started at a low 17 dBA@1m SPL. In ECO mode, the absence of electronic noise was striking. This is only the second time I’ve encountered such a lack of electronic noise from a power supply, and surprisingly, it’s happened twice in a row. The previous electronically-silent PSU was the last one I tested, the Seasonic X1050. The noise of the Kingwin LZP-1000 at <500W in ECO mode is similar, well below the 10 dBA noise floor of the anechoic chamber, and inaudible even from under a foot away.

When the fan came on at 500W, it did not stay on continuously. It ran at a speed slightly higher than at normal default, but for only a couple of minutes, then turned off for about five minutes before turning back on again. With the fan running, the relatively cool ambient air quickly cooled the interior of the PSU to 45~50°C, which then triggered the fan to turn off. The measured noise when the fan did come on was about 20 dBA@1m, not quiet enough to go unnoticed (by me, anyway) but smooth and innocuous.

You will notice that there are two temperature numbers at each power level, too. They refer to the temperature at the exhaust vent in normal and ECO mode. When the fan is not running, the heat simply rises up through the fan via convection, so the exhaust vent stays cool. I did record intake temperatures (an inch above the fan) and naturally, it was much higher when the fan was not running, much higher than the exhaust vent temperatures. But when the fan started to run, the heat in the PSU was forced out the exhaust vent, so the temperature naturally shot up. In any case, only at extended full power would I have any concern about whether the PSU keeps itself cool enough. If used in a typical high performance case with a direct air intake for the PSU fan, only extended super loads in very hot weather is likely to risk overheating shutdown in the LZW-1000.

IN THE HOT BOX

The PSU is tested briefly in the hotbox only to check on what happens to noise, fan speed and temperatures when it is used in an outmoded case design which keeps the PSU drawing air from inside the PC case. In this test, roughly 30~50% of the air heated up by the output of the PSU ends up being evacuated through the PSU. This is obviously a lot of heat at full 1000W, and the PSU still has to deal with its own internal heat.

Even in the hot box, the LZP-1000 fan did not turn on except at high test loads. The 20 dBA@1m cited for the 500W load is only true part of the time: It stayed off for some 10 minutes at this load before the fan turned on, and it stayed on for only about two minutes. The total time at this load was around 20 minutes, and the fan did not come on again. But after extended operation in the hotbox at 500W load and higher, with the exhaust temperature reaching as high as 70°C, the fan came on and sped up to a higher speed. It stayed at this speed for a good 7~8 minutes before slowing and quieting to 17 dBA@1m, but it did not stop spinning as long as the load was 500W or higher in the hotbox. Even at full power in the hotbox, the noise level never exceeded 25 dBA@1m, and the overall quality of noise was smooth and benign, without tonal peaks.

The main difference compared to outside the hot box was that the fan ran slightly faster (noisier) at ~500W. Outside that power range, there was no appreciable difference in acoustics.

Kingwin LZP-1000 SPL: In Hot Box vs. Out
Power load	90W	150W	200W	250W	300W	400W	500W	700W	1KW
out	<10	<10	<10	<10	<10	<10	17*	23*	25*
in hot box	<10	<10	<10	<10	<10	<10	20*	24*	25*
Measurements are in dBA@1m * See note in text above.

TOO HOT?

So given the relatively low speed of its fan, is the LZP-1000 is adequately cooled at the higher power levels? Consider that while Seasonic X1050 fan was probably spinning at >2000 RPM at full load, while the LZP-1000 fan seemed to be no higher than perhaps 1200 or 1300 RPM. A complete record of exhaust temperatures were not kept, but the highest exhaust vent temperature at full load was around 70°C, and it would probably climb higher if that load was maintain for a longer period — at most power levels, the test is run for 20~30 minutes, long enough to stabilize temperature most of the time.

• Does efficiency suffer? Well, yes, in my testing it did drop a bit, but only by about a percentage point, at 700W and 1000W.
• Does this matter? Perhaps if that power load is often and steadily maintained.
• Will such modest forced air cooling cause premature heat-related component failure in this PSU? An answer would only be a conjecture, but the 5-year warranty suggests confidence in the product’s longevity by Kingwin.

To extend that last comment, my hunch is that Kingwin is making a calculated risk that…

• Few users will actually use this PSU in a system that demands anything near the full the rated output for long periods. To reach anywhere close to 1000W peaks (never mind sustained loads), my guess is that you’d need the hottest Intel or AMD CPU overclocked to the limit (for perhaps 180W peaks), and at least two of the hottest most power-hungy video cards (for ~600W peaks) all cooled with a massive watercooling system (drawing maybe 60W). The power draw of the motherboard, HDDs, SSDs and other components are not likely to amount to even a hundred watts. This might net >900W peaks in extreme gaming. How many such systems are in actual use out there? Not many. The cost is high and the returns in perceivable gaming performance are diminshed.
• The cooling required for other components to run stable in such systems will ensure that the PSU only needs to take care of its own heat. No serious gaming case forces the PSU to draw air from inside the case.
• So, overheating due to actual power load is not much of a risk. Overheating by exposure to extremely hot weather (say >35°C) is also very unlikely: Whoever can afford such a powerful PC can also afford air conditioning. No one wants to sit at a hot gaming terminal with sweaty hands.
• The cost of few PSUs that might fail early due to the low fan speeds will be more than compensate by increased sales and increased penetration into the silent PC market.

COMPARISONS

The comparison table below shows the SPL versus Power Load on
PSUs tested in ambient room temperature, typically 20~24°C. It is most relevant when the PSUs are used in modern cases that provide wide open access to cooler outside air for the PSU cooling fan.

It’s difficult to rank them, as
the measured SPL varies with power load. The units which are quietest at minimum
load are not always the quietest at midload (150W~400W), which may make them
louder in actual use. Then there’s the noise level at 400W and up, which will
determine the quietest PSUs for high power gaming rigs, during actual gaming.

The LZP-1000 lands near the very top. The 20 dBA@1m SPL shown for 500W load is higher than actually perceived because it is the highest measured value when the fan is running — but the fan typically runs only about a third of the time at this load (in 22~24°C ambient). When the fan is not running, the noise level is actually lower than those of the fanless models, so it could arguably be placed at the very top of the table.

PSU Noise (dBA@1m) vs. Power in Ambient Room Temperature
Model	90W	150W	200W	250W	300W	400W	500W	6-700W	850W	1KW
Seasonic X-400/460 Fanless	<10*	<10	<10	<10	<10	<10	<13	n/a	n/a	n/a
Kingwin STR-500 Fanless	<10*	<10	<10	<10	<10	<10	<13	n/a	n/a	n/a
Kingwin Lazer Platinum LZP-550	<10*	<10	<10	<10	<10	<10	16	n/a	n/a	n/a
Kingwin Lazer Platinum LZP-1000	<10*	<10	<10	<10	<10	<10	20	23	24?	25
Seasonic X-1050	<10*	<10	12	12	13	14	16	26	40	40
Silverstone ST50NF Fanless	11	11	11	11	15	15	16	n/a	n/a	n/a
Enermax Modu/Pro87+ 500	11	11	11	11	11	11	18	n/a	n/a	n/a
Corsair AX850	<10	<10	<10	11~13	12	13	17	24	35	35
Seasonic X-650	<10	<10	<10	<10	<10	16	27	32	n/a	n/a
Nexus NX-5000	11	11	12	12	12.5	14	19	n/a	n/a	n/a
Antec CP-850	12	12	12	12	12	14	20	24	40	40
Enermax Eco80+ 500W	<11	12	12	16	20	23	28	n/a	n/a	n/a
Antec TP-750	12	12	12	14	15	27	31	40	n/a	n/a
Cougar GX-700	15	15	15	17	21	25	35	35	n/a	n/a

The comparison table below shows the SPL versus Power Load data on all the
PSUs tested in the hotbox. This is relevant only when the PSU is used in cases with poor ventilation, and forces the PSU to draw air from inside the case.

The Kingwin Lazer Platinum LZP-1000 acoustics in the hotbox is at the top of the pack, aside from the completely fanless Seasonic X-400 (and X-460). At every load up to its maximum, the unit is quieter than all other tested PSUs, even the just-celebrated Seasonic X1050. Above 500W load, the LZW-1000 has no acoustic comepetition at all. The 25 dBA@1m SPL at 1000W is simply amazing.

PSU Noise (dBA@1m) vs. Power in Hotbox / Anechoic Chamber
Model	90W	150W	200W	250W	300W	400W	500W	6-700W	850W	1KW
Seasonic X-400/460 Fanless	<10*	<10	<10	<10	<10	<10	<13	n/a	n/a	n/a
Kingwin STR-500 Fanless	<10*	<10	<10	<10	<10	<10	<13	n/a	n/a	n/a
Kingwin Lazer Platinum LZP-1000	<10*	<10	<10	<10	<10	<10	20	23	24?	25
Seasonic X-1050	<10*	<10	12	12	13	16	16	28	37	40
Kingwin Lazer Platinum LZP-550	<10*	<10	<10	<10	<10	16	22	n/a	n/a	n/a
Silverstone ST50NF Fanless	11	11	11	11	15	15	16	n/a	n/a	n/a
Enermax Modu/Pro87+ 500	11	11	11	11	14	20	23	n/a	n/a	n/a
Corsair AX850	<10	<10	12	15	18	25	35	38	39	n/a
Seasonic X-650	<10	<10	12	14	16	31	31	32	n/a	n/a
Nexus Value 430	11	11	16	18	18	19	n/a	n/a	n/a	n/a
Nexus NX-5000	11	11	12	14	22	24	25	n/a	n/a	n/a
Antec CP-850	12	12	12	14	14	26	40	44	45	n/a
Enermax Eco80+ 500W	<11	12	16	19	26	32	33	n/a	n/a	n/a
Seasonic M12D 850W	14	14	14	14	14	24	37	42	42	n/a
Antec TP-750	12	12	14	14	18	33	40	40	n/a	n/a
Chill Innovation CP-700M	15	15	15	15	17	30	34	34	n/a	n/a
Antec Signature 650	15	15	15	18	18	28	36	47	n/a	n/a
Coolermaster M700W	14	14	18	21	25	27	34	34	n/a	n/a
Cougar GX-700	15	15	18	20	25	32	35	36	n/a	n/a
SilverStone DA700	18	18	18	18	23	32	35	41	n/a	n/a
Nexus RX-8500	14	14	17	22	28	32	32	33	33	n/a
NesteQ ECS7001	22	22	22	21	23	25	36	37	n/a	n/a
PCPC Silencer 610	20	24	24	24	24	30	40	50	n/a	n/a

Caution: Please keep in mind that
the data in the above table is specific to the conditions of our test setup.
Change the cooling configuration, the ambient temperature and any number of
other factors, and you could change the point at which the fans start speeding
up, as well as the rate of the rise in speed. The baseline SPL is accurate,
however, probably to within 1 dBA.

CONCLUSIONS

The Kingwin Lazer Platinum LZP-1000 easily jumps to forefront of quiet, powerful PSUs. The notable merits are numerous:

• 94% peak efficiency (at the important mid loads)
• Very good voltage regulation
• Excellent noise & ripple
• No audible electronic noise at any load
• Inaudible at <500W
• Quieter than all other PSUs at >500~600W
• Amazingly quiet even at 1000W

As with previous Seasonic and Kingwin models, high efficiency is what makes the semi-passive fan cooling scheme workable… even with the small heatsinks. There is so little heat to dissipate, even at very high power, less in this 80 Plus Platinum level PSU than any other we’ve tested thus far.

If installed in a system with long term average power draw of 700W or higher, one might have thoughts about the risk to longevity with the constant heat load. This would be especially true in a tower case where the PSU is mounted conventionally at the top back corner. Such cases are increasingly out of favor with DIY builders, however, and the majority of high performance cases now place the PSU at the bottom back corner. Those who live in 220~240 VAC service areas get the benefit of efficiency that is even higher, 96% at the peak.

The absence of electronic buzz, whine, or hum was notable. This is only the second PSU sample to exhibit such stony silence in 10 years of testing PSUs at SPCR labs. This quality is a great match to the l cooling fan. which does not turn on till 500W or higher in normal ooperation, and stays quiet and smooth throughout the power range.

The Seasonic X1050’s mid-power efficiency is lower by a couple points, and above 500~600W, the Kingwin is a lot quieter. But the Seasonic casing is obviously higher quality, as is its overall finish, and there’s no question this is an unquantifiable but significant aspect of a product’s overall appeal. About the only other quibble I can mention is that the many permanently attached cables make the LZP-1000 much less of a modular PSU than the Seasonic X1050, where all the cables are removable. For most users, this is a pretty minor quibble in a product that is exceptional in acoustic, efficiency and electrical performance.

Kingwin LZP-1000 Balance Sheet
Likes * 90~94% efficiency in typical use * Silent in typical use * Super quiet even at 1000W! * Excellent electrical performance * Semi-passive cooling really works; fan runs only when needed. * Modular cables * 5-year warranty	Quibbles * Five permanently attached cables.

Much thanks to Kingwin Technology for the review sample.

Kingwin Lazer Platinum LZP-1000 receives the SPCR Editor’s Choice Award

* * *

SPCR Articles of Related Interest:
Seasonic X-1050 PSU: Gold at Kilowatt+
Corsair Gold: AX850 Power Supply

X-650: Seasonic hits Gold
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Fanless PSU Torture Test Shootout
Kingwin LZP-550 80 Plus Platinum
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SPCR PSU Test Rig V.4

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