A 100% fully modular PSU available in 550W, 650W and 750W versions. Is this the most affordable PSU you can get? Let’s find out!
Product on Review: OCZ ZT Series
Manufacturer & Sponsor: OCZ Technology
Street Price: £69.99 inc. VAT (GBP)
So far this year OCZ have been on top form, they have furnished the market with a number of innovative products. Whilst these products have mainly been concerned with the storage sector OCZ have also been revamping their various PSU series. The series we are to take a look at today may not be classified as innovative but it certainly hopes to carry on a good thing.
The ZT Series is found within OCZ’s High Performance category and is significant due to its fully modular cabling system. Most PSUs that name themselves modular refer to a certain group of cables that are removable but the ZT boasts a completely modular configuration – even the motherboard ATX cable is detachable. The ZT series adopts 80 Plus Bronze certification and is available in following variants 550W, 650W, and 750W. Today we will be taking a look at the first model and lowest rated wattage – 550W. Ideal for those who are looking to build a gaming system with a powerful graphics card and typical assortment of drives and devices.
The ZT series is the superb choice for performance and power users who need solid, reliable PSU. With a completely modular design, ZT Series keeps your internal case environment organized by eliminating wire clutter and improves airflow by using only the cables you require. Kept supremely cool with a load-controlled 140mm fan, the OCZ ZT Series PSU was engineered to be ultra-quiet by eliminating distracting noises from your PC when working or gaming. With an 80-Plus Bronze Certification featuring up to 85% efficiency under typical load environments, this power supply remains rock solid and stable.
Features & Specifications
• Available in 550W, 650W, 750W
• Single +12V rail for efficient power distribution
• Heavy-duty protection circuitry
• Fully Modular Cabling System
• 80-Plus Bronze Certified (85% efficient at typical load)
• 140mm ball-bearing fan
• Dimensions: 150 x 86 x 175mm (W x L x H)
• Rated at 45°C ambient
• Premium 105°C electrolytic capacitors
• Erp compliant, low power usage in standby mode
• Active PFC
• ATX 12V 2.2 Compliant
• MTBF: 100,000 hours
• 5-year warranty
550W Connectors
• 1 x 20+4-pin ATX
• 1 x 4+4-pin ESP/12V CPU
• 2 x 6+2-pin PCI-E
• 6 x 4-pin Peripheral
• 6 x 5-pin SATA
• 1 x Floppy
Packaging & Bundle
The ZT is has been given the colour of yellow to identify that it is within the “High Performance” segment and is modular. On the packaging OCZ are keen to get across that the ZT is 100% modular, not just part modular – every single cable even the 24-pin is removable. Also on the packaging is the 5 year warranty and 80 Plus Bronze badges.
ZT packaging – a clear message, this is 100% modular
Inside the packaging there is a small bundle that consists of the following items: OCZ Box containing all cables, instructions manual, ZT PSU in velvet drawstring bag.
ZT bundled items
Taking a closer look at the cables included within the bundle, as mentioned earlier we even have the 24-pin ATX cable here. All of the cables excluding the Molex and SATA are wrapped in a sleeve. The Molex and SATA cables have been given an insulated black covering meaning there is more flexibility and they are easier to hide away inside the case. The cables included are:
• 1x 24-pin ATX motherboard power
• 1x 8/4-pin CPU POWER (EPS/E-ATX)
• 2x PCI-E 8-pin
• 2x Molex (each with 3 plugs)
• 2x SATA (each with 3 plugs)
• Power cable
Cables that are included are all modular
Closer Look
Removing the PSU from its protective bag we are met with a black unit that has the yellow accents to show what range this PSU is from. Both sides of the ZT have the same graphics, the alternate side to that pictured below has the graphics upside down – meaning that whatever orientation you choose to have the unit the text will be facing the correct way.
An overview of ZT
The ZT takes advantage of a 140mm fan for cooling internal components. This fan has a grill and the OCZ logo has been placed right in the middle. When we open the unit up in the next section we will take a closer look at this fan.
ZT uses a 140mm ball bearing fan
Lastly there is the modular panel for connecting all of the cables. The PCI-E are set apart in a white colour to easily distinguish them and the 24-pin ATX slot runs vertically on the far right of the unit. Due to ZT being 100% modular it means the consumer can choose exactly what cables are needed to power their system rather than having cables that are hard-wired and unneeded.
The modular panel on ZT
Internals
Taking apart a PSU is a risky business. Not only does it void your warranty but you could also potential damage components inside due to them being totally exposed. Do so at your own risk!
Once all 4 screws have been removed we can delve into the inner workings of the ZT. The fan that OCZ have used for the ZT is in fact a Yate Loon D14BH-12. Amongst enthusiasts, Yate Loon have a solid reputation for having a series of fans that not only push plenty of air but do so at a lower noise compared to rivals. They are also very easy to get hold of and are inexpensive. This particular model is 140mm in size and is ball-bearing.
140mm Yate Loon ball bearing fan
The unit itself is well organised and has two separate heatsinks for cooling internal components. OCZ or rather Great Wall who are the OEM for this and many other units in the OCZ line have equipped the ZT with Over-Voltage , Over-Temperature, Over-Current, for all rails.
An overview of the internals
105C CAPs
The hold-up Capacitor is delivered via Teapo (560μF, 420V, 105°C).
Teapo 105C hold-up CAP
Testing Methodologies & Results
Our testing methodology for testing Power Supply Units is limited to the multi-meter to show each rails performance due to us not having access to an ATE load tester. We are making plans to invest in equipment as we were directed by Cooler Master when Simon visited their test labs in June 2010.
Although this does constrain us slightly we can still monitor fluctuations on the rails and give the unit a good assessment when we feature it in one of our builds. The way the testing will run is simple, voltages will be observed at idle wattage and then a single GPU will be installed within the system and a combination of OCCT and MSI Kombustor will be executed to provide simulation with just 1 GPU usually another GPU would be added to the system in order to generate more power draw but since this unit is 550W there is no need to do this. 1 GPU generates around 450W whilst adding another and the total usage exceeds 750W.
To add further power draw the CPU will be overclocked to maximise power consumption and strain. This should give us a good indication of how the OCZ ZT 500W will perform under gaming stresses and beyond. This is a good representation of real-world analysis.
System Components
CPU Intel Core i7 2500K (with OC 4.5GHz)
Motherboard ASUS P8P67
Graphics NVIDIA GTX 480
Memory 8GB Kingston HyperX 1600MHz CL9
HDD 2 x Samsung Spinpoint 500GB SATA-II
PSU OCZ ZT 550W
We all know how Fermi is notorious for its big power draw! As I mentioned there is no ATE load tester available so generating as much power as possible is key to observing the fluctuations on the rails.
For voltage tolerance levels, ATX specify that a 5% variable fluctuation is acceptable. (Form Factors – ATX Specification PDF – Page 10). So what this means is:
3.3V Rail – 3.135V – 3.465V acceptable
5V Rail – 4.75V – 5.25V acceptable
12V Rail – 11.4V – 12.6V acceptable
Idle test – The system settles in windows without any applications or stressing. 1 GPU (215W)
Single GPU – OCCT/MSI Kombustor run for 10 minutes (422W)
The ZT 550W does an exceptional job throughout the voltage variance testing, all of the rails – 3.3V, 5V and 12V remain in the realm of ‘acceptable’ according to the ATX standards.
At 76% load the 140mm Yate Loon inside did generate unwanted noise levels.
Conclusion
Choosing the right PSU is an important decision for the enthusiast because it is the backbone of any system. Buying an inferior, no-frills unit brings with it many consequences – some of which can be catastrophic. I’ve personally read of many stories of various individuals who have been strapped for cash and gone down this route, these cheaper units can often blow and when they do, they will take everything with it. So you may think spending all of your money on the core components like CPU, GPU, motherboard and then very little on the PSU is a good thing – this may change when it goes up in smoke!
Today’s review sample is a fine example of what a PSU should and could be. The ZT’s selling point is quite obvious from the packaging – its 100% fully modular. Most units that claim to be modular are only in fact part-modular, meaning that some of the cables are still hardwired into the unit. Even the 24-pin ATX cable on the ZT is removable, showing just how flexible this product can be. This means that creating a tidy interior within the case can be easily achieved, unwanted cables can be stored away when not used – the idea of a fully modular PSU is just great.
Though we aren’t able to test every aspect of a PSU we did examine the ZT’s voltage variance during real-world testing and the results were pleasing. All rails remains within the ATX specifications and fluctuations were only minor. The only slight niggle being that at 75%+ the unit’s 140mm Yate Loon fan did generate some ramp up noise.
Priced at £69.99 inc. VAT the ZT 550W is an affordable PSU, not only is it within the same price-range as some of the other 500W PSUs that aren’t modular it obviously adopts this fully modular characteristic. There really is no excuse for not buying a decent branded PSU.
Pros
+ Fully modular
+ Good performance
+ 5 Year Warranty
+ Reasonable Price
Cons
– No cable carry case
– Noise under load
+ Fully modular
+ Good performance
+ 5 Year Warranty
+ Reasonable Price
Cons
– No cable carry case
– Noise under load
