OCZ Z-Series Z1000M 1000W ATX PSU
Simulated Load Testing
To provide accurate and consistent results in all of our PSU testing, Overclock3D uses professional grade DC electronic load equipment capable of placing a sustained load of 3690w across a total of six rails (including +5vsb and -12v) on the PSU! This is achieved by using a combination of SunMoon and Analogic electronic load equipment which allow us to adjust amperage loads in increments as small as 0.01A while also measuring voltage and wattage readings on-screen.
During today’s tests, we will be placing the OCZ Z-Series Z1000M under 25%, 50%, 75% and 100% load levels at both room temperature and inside a hot box regulated to a temperature of around 50°C. Additional ‘Cross Load’ and a ‘Max Load’ tests will also be performed under these conditions to simulate how the PSU reacts to heavily uneven loads as well as running above its specified output.
OCZ Z-Series 1000w Results @ Room Temperature
DC Watts
Exhaust
(Low)
256w
31.1°C
(Med)
521w
33.0°C
4.96v
(High)
758w
34.7°C
(Full)
1002w
36.8°C
(x-load)
183w
32.5°C
(x-load)
939w
35.7°C
(MAX)
1268w
38.9°C
OCZ Z-Series Z1000M Performance Overview
T1-T4
T1-T4
T1-T4
T1-T2
T1-T2
T1-T4
Firstly before we start, let me introduce you to our new performance overview chart. This chart is designed to give you an idea of a PSU’s performance at a glance without having to navigate through the full set of test data. The first five rows labelled Diff. T1-T4 represent the voltage difference between Test 1 and Test 4 on each of the PSU’s rails. The lower the percentage, the more stable you can assume the PSU is in a normal operational environment. Average efficiency on the other hand is calculated by taking the efficiency results from Test 1 to Test 4, adding them together and then dividing by 4. Of course, I still recommend that you take a look at the full set of test results for an idea of the actual voltage values and results in cross-load or max-load situations, but I hope you will agree that the performance chart is a worthy addition to the results data.
Now on to the actual results we can see quite a drop in the voltage of the 3.3v rail from Test 1 to Test 4 with a difference calculated at 5.95%. This is quite high in contrast to a lot of the other 700w+ PSU’s we’ve reviewed recently which have managed to limit fluctuation to around 2%. The +5v rail keeps things just a little bit tighter with a difference of 4.15% between the T1 and T4 results, but once again this is still a few percent higher than its peers. Finally, the +12v rail is slightly more respectable with a fluctuation of 1.71%, equating to a difference of 0.21v between Test 1 and Test 4.
Moving on to the cross-load tests 5 and 6, all of the rails cope very well with no see-saw effects to be seen. This is extremely good as most PSU’s tend to lose control of at least one of the rails in this situation (usually the -12v) sending the voltages sky-rocketing. The Max-Load results in Test 7 show us exactly what the Z1000M is capable of by managing to sustain a maximum load of 1268W with a massive 85A of that all on the +12v rail. The only issue here is that the +3.3v rail is once again quite low at 3.14v.
Efficiency during all tests was just as promised with the unit managing at least 90% efficiency across all of the standard tests. Only in Test 5 when a heavy load was applied to the +3.3v and +5v rails did the unit dip all the way down to 82.43% efficiency. However, as these tests are not part of the usual 80PLUS certification, this does not affect the Z1000M’s gold ranking. Nor will it be an issue during general day-to-day use.
OCZ Z-Series 1000w Results @ 50°C
DC Watts
Exhaust
(Low)
255w
47.0°C
(Med)
508w
49.0°C
4.95v
(High)
758w
54.0°C
(Full)
1001w
55.6°C
(x-load)
183w
50.2°C
(x-load)
939w
57.1°C
(MAX)
1268w
63.3°C
OCZ Z-Series Z1000M Performance Overview
T1-T4
T1-T4
T1-T4
T1-T4
Placing the Z1000M in the OC3D hot-box dialled up to an ambient temperature of 50.0°C does very little to change the results. Almost all of the voltages are identical to the room temperature tests with the exception of a few that are only 0.01v lower. The efficiency levels also take a dip by around 1% during some of the tests, but this could equally be attributed to general fluctuation rather than any performance drop inside the unit. Now on to the ripple results…
OCZ Z-Series Z1000M Scope Results @ 50c
(Low)
(Med)
(High)
(Full)
(x-load)
(x-load)
(MAX)
For those of you not familiar with the term ‘ripple’ (other than in a flakey chocolate bar), this refers to the small fluctuations in voltage that occur in all PSU’s on a milisecond scale. Large quantities of ‘ripple’ on a PSU can damage or kill components in your PC over time and therefore testing a PSU’s performance in this area is just as important as any other part. Unfortunately ripple cannot be measured using a standard multimeter and requires a specialist device called an oscillioscope. The results you see above are taken from our Rigol 25Mhz 400MSa/s scope that can save ‘screenshots’ of its data to a USB memory stick.
ATX specification states that ripple should be no higher than 50mV on the +3.3v/+5v rails and 120mV on the +12v rails. As we can see from the results in Test 1 to Test 4, the OCZ Z1000M manages this with ease. The +3.3v rail begins at a very impressive 16mV in Test 1 and slowly creeps up to 40mV by Test 4, while the +5v rail starts at 11mV and only increases slightly to 18mV. The +12v rail is also very respectable, with a maximum Vpp of just under 60mV in Test 4.
Only when we move on to Test 7 does the ripple jump up significantly with 52mV ripple on the +3.3v rail and 90mV on the +12v rail. But by this time the Z1000M is running 268W above its rated output, so to stay pretty much within ATX spec still is a big accomplishment.
