Although the market is pretty saturated as far as PSUs are concerned, with all segments well-covered, manufacturers are still churning out new models in the desire to satisfy the customers’ needs as well as possible and present a product for every budget. OCZ has built a decent reputation in the past few years, both by its aggressive approach on the SSD market and their PSU product gamma. As the models from the ZX series are made to satisfy even the most demanding of users and cater for the high-end bit of the market, OCZ had to create the ZT product line, targeting the mid-range and with an excellent price/performance ratio.
The ZT series contains three models, working at 550 W, 650 W and 750 W, all of which have a completely modular cable design, the 80 PLUS Bronze efficiency certificate, five years’ warranty and a relatively accessible price, offering a lot of bang for your buck. The model we received for testing has a capacity of 650 W.
The box is significantly larger than the PSU itself, and we found out why soon upon opening it – the left half contains the PSU itself, wrapped in a neat plastic bag with a rope on top, while the other half contains another smaller black box with all the necessary cables. Besides, there’s also a plastic bag containing a few plastic cable holders, mounting screws, the manual, and of course the mains power cable. The bundle provides a total of twelve modular cables, plus a molex-to-floppy converter, should anyone ever need one. It’s interesting that certain cables, such as the 24-pin, CPU and PCI-E ones, are covered by black protective nets, while SATA and molex ones don’t have them, being flat. Besides the one 20+4-pin ATX and two 4+4-pin connectors, there are nine more SATA connectors, six peripheral molex and two 6+2-pin PCI-E cables for auxiliary graphics power. As you can instantly tell from the number of PCI-E cables/connectors, the PSU hasn’t been designed with SLI/CrossFire exhibitionism in mind, but as it turned out, the PSU can run two Radeon HD 7970 cards simultaneously without much trouble.
The unit itself is uniformly black with a nice matte finish, while the sides contain stickers with attractive black and yellow markings and motives. Cooling is entrusted to the 140 mm double ball-bearing fan with automatic RPM regulation, which ensures quiet operation and maximum airflow when needed. The PSU itself is 175 mm long, which places it in the larger model category, but it should still fit in any modern enclosure. The back side houses the power connector and the on/off switch within the protective exhaust net.
This PSU’s internal architecture represents the solution with a single +12 V rail, which can provide up to 54 A according to specs. This should be enough for any CPU/graphics combo, even in the case of the strongest hexa-core CPU coupled with the very best graphics card. The entire ZT series is 80 PLUS Bronze-certified, which means that the PSU can provide 85% energy efficiency at a 50% load, but also that it’s made in accordance with the ErP (Energy-related Product) directive, which means that the unit consumes less than 1 W in passive standby and off modes. Of course, active PFC (Power Factor Correction) is a given, as is the standard set of protective measures such as OPP (Overload Protection), SCP (Short Circuit Protection) and others (OVP, OCP).
|OCZ ZT 650W||Idle (97W)||Full load - Linx (237W)||Full load - Furmark (662 W)||Full load - Linx & Furmark (670 W)|
|PCI-Express 12V (GPU1/GPU2)||12,22 / 12,22||12,21 / 12,19||12,4 / 12,5||12,04 / 12,1|
|Test machine: Intel Core i7 3960X 3,3 GHz, Sapphire Pure Black X79N, 4x 2GB Kingston HyperX 2133, 2x AMD Radeon HD 7970 CrossFire, WD500 GB blue|
When we switch from the paper sheet to the real world, there really isn’t anything to reproach to this PSU, especially when you see that OCZ ZT 650 W managed to handle our test-system with relative ease – not even a hexa-core Core i7-3960X CPU coupled with two Radeon HD 7970 graphics cards in CrossFire and four modules of 2 GB RAM each couldn’t bring this PSU to its knees. Linx and Furmark even managed to push the total consumption over the PSU’s limit when running simultaneously, but ZT 650 W still managed to pull through.
|Declared power||650 W|
|Current on +12V/+5V/+3,3V
||54 / 30 / 24 A|
|Connectors||MB 20+4-pin x 1 ; CPU 4+4-pin 12V x 1 ; PCI-e 6+2-pin x 2 ; SATA x 6 ; Peripheral 4-pin x 6 ; Floppy 4-pin x 1|
||150 x 86 x 175 mm|
|Protections||OVP / UVP / OPP / OTP / SCP|
|Efficiency||80 PLUS Bronze|
|Price||~ 85 €|
All things considered, this is an exceptionally high-quality PSU, which offers fully modular cables and very good performance at a decent enough price. The maximum 54 A on the single +12 V rail is obviously enough to achieve impressive results, and it’s really a pity that only two 6+2-pin PCI-E cables are available, as the PSU even managed to power two very demanding graphics cards at the same time. Add to this he 80 PLUS Bronze efficiency certificate and a five-year warranty period, and you have a definite winner in OCZ ZT 650 W. Our warmest recommendation.