OCZ Z Series Z1000M (1000W)
Having started as a maker of memory modules and coolers, OCZ Technology has been constantly expanding its scope in the last couple of years. Particularly, it has begun to produce power supplies. Today I will discuss the 1000W model from the Z series, and we will also publish a review of a few affordable power supplies from OCZ, with wattage ratings of about 400W, in near future.
The PSU comes in a medium-sized black-and-yellow box.
The Z1000M is one of the two smallest products in today’s tests, the Akasa PowerMax being the other one. Its dimensions are actually determined by the size of the cooling fan.
Like in Enermax models, the PSU case is rolled in near the fan to reduce the gap between the fan and the panel. This should lower the noise produced by the fan.
The PSU is modular and offers eight connectors for detachable cables. It is not good that the 6-pin connectors for graphics card and peripheral cables are different colors and voltages, but have identically positioned keys. It means you must be very careful when connecting your components to this PSU as it offers neither mechanical nor electrical protection against incorrect connection of the power cables, which may, for example, destroy your HDDs.
The PSU is equipped with the following cables and connectors:
- Mainboard cable with a 24-pin connector (55cm)
- CPU cable with a 4+4-pin connector (60cm)
- CPU cable with an 8-pin connector (60cm)
- Two graphics card cables with one 6+2-pin connector on each (61cm)
- One cable with three SATA power connectors (60+18+18cm)
- Four connectors for additional graphics card power cables
- Four connectors for additional peripheral power cables
Included with the PSU are:
- Four graphics card cables with one 6+2-pin connector on each (58cm)
- One cable with three Molex connectors and one floppy-drive plug (53+18+18+18cm)
- Three cables with three SATA power connectors on each (48+18+18cm)
Although there are both 8- and 6-pin connectors for graphics cards in the PSU, the included cables all had one 8-pin and one 6-pin end. Hopefully, it is only a problem with the accessories to my sample of the PSU and the Z series will come to shops with a correct selection of cables.
It is good that there are more SATA than PATA power cables. The four SATA cables will be most suitable for RAID arrays. The PSU also allows to connect up to three top-end graphics cards without power adapters.
The only thing that I don’t quite grasp – not only in OCZ products – is that there are two fixed CPU power cables. There are very few mainboards with two connectors (mostly dual-processor server-oriented models), so most users won’t use one of these cables. Why not make it detachable then?
The detachable cables come neatly packed into a nice pouch.
The interior design is typical of many modern PSUs. The power components are distributed among three independent heatsinks. There are no noticeable innovations in the Z series. It is an ordinary PSU with one transformer, active PFC and dedicated voltage regulation on magnetic amplifiers.
The PSU is manufactured by Sirfa which had been a Sirtec fab before 2008 but now is an independent venture.
The PSU’s specs indicate no splitting of the +12V rail into “virtual” output lines. This has no effect on stability but solves the possible problem when the PSU might shut down due to overload on one of the individual +12V lines. The PSU can yield its full 1000W via the +12V rail, so its effective output power equals the specified value.
Together with an APC SmartUPS SC 620 this power supply worked at loads up to 415W when powered by the mains. They switched to the batteries normally but were not stable even at 300W then. Therefore, I’d recommend a UPS with sinusoidal output voltage for the Z1000M.
Output Voltage Stability
The +3.3V voltage goes beyond the permissible 5% limit under high load. On the other hand, you won’t have such load distribution in modern PCs which mostly consume from the +12V rail. This is indicated by our three reference configurations: with each of them the voltages stay within 2-3% from their respective nominal values.
Output Voltage Ripple
There are periodic spikes of voltage on the +3.3V rail that violate the permissible limit, but that’s not a big problem. The +5V voltage ripple is within the allowable limits. On the +12V rail the voltage ripple is very low although this rail has over 80% of the total load in the test.
The PSU is cooled by a 135x135x25mm fan from Globe Fan. About a quarter of it is covered with a celluloid triangle as in the Hiper model produced by Sirtec. So, the kinship of the two companies can be observed in small things, too.
The fan starts out at 960rpm and reaches 1000rpm at a load of 650W. Thus, the Z1000M is somewhat quieter than most of the PSUs in this review, even though not by much.
Efficiency and Power Factor
It is a second model out of 14 whose efficiency is higher than 90%. The peak efficiency is 91.7%. And at full load the PSU is 87.7% efficient. Thus, the OCZ Z1000M is even a tiny bit better than the Enermax Revolution 85+ that has been the best PSU in this test among all we have ever tested and also the only model to be more than 90% efficient.
So, the OCZ is quite deservedly certified to comply with the 80 PLUS Gold standard. Its power factor is somewhat worse, though. It varies from 90 to 95% through most of the diagram.
The standby source of the Z1000M is rated for a current up to 6A. Its voltage bottoms out to 4.9V under full load, which is much higher than the permissible minimum.
Although we didn't find any outstandingly unique features, OCZ has produced a very good power supply. Quiet and stable, it offers plenty cables and connectors and easily delivers its specified output power.
It should be noted that the OCZ Z series is the second PSU series (after the Enermax Revolution) to show an efficiency of over 90% in my tests. This level is going to be the goal for many makers now just as they all struggled to reach the 80% mark a few years ago. That’s how fast it goes as I can even recall those times when a 70-75% efficient PSU was considered mainstream.