Many of you would agree with me when I say that here in India, PSU is a component which was never given much importance or taken seriously till a few years ago.
Few years back, the concept of a standalone, high performance PSU was unknown to many here. It was only after high end hardware like Quad core CPUs, high end graphic cards, SLI, Crossfire, Dual GPU single slot cards started making an appearance that people realized the need of a good quality PSU.
Conventionally, PSUs would be bundled with the chassis and usually they would be rated at 300W or 400W which people thought would suffice and it did to some extent.
In reality these crappy bundled PSUs could hardly deliver even 180W of real power. This was exposed when people bought high end setups and their PSUs just couldn't handle their setups.
First it was the local chassis brands that started introducing high end PSUs which were rated at 500/600W. Although they were slightly better than the bundled ones, it was still a long way to go before we saw any REAL high end ones.
Sometime later, Antec entered the Indian market and that opened up the option for buyers to spend their hard earned money for buying good quality power supplies.
Later on many known brands like Coolermaster, Tagan, and Corsair etc. entered the Indian market.
Many of you may not be aware of a Taiwanese company called ‘Seventeam’ who are known to make some top quality PSUs for quite some time now.
What we have with us today is a PSU from Seventeam, the ST-750Z-AF which is a Modular PSU rated at 750W.
Before proceeding with this review, some information about Seventeam,
‘Seventeam Electronics was founded in 1986. Its headquarters and R&D center are based in Taipei,Taiwan and currently has instant sale and logistics network in major countries around the world.
Seventeam Electronics is the leading company in switching power supply products. Its leading expertise also dominates the markets in developing high performance, high watts, high stability and environmental products. It promotes the technology that is quiet and energy smart, furthermore, it tried hard to promote the concept of Semi-Fanless innovation. These features of the company are undoubtedly the strong forces in driving computer user experiences and the industry itself forward in the age that emphasizes computer speed.
The power supply products we offer include the power supply for PC and customized power supply for IPC (for industrial and server uses). We dedicate ourselves in promoting the global sale and service network of all Seventeam’s products. Our products are used by various global leading partners in system integration and we also offer multi-faceted OEM.ODM services’
Now that you are familiar with what Seventeam is and what we are going to review today, lets proceed on with the actual review
[BREAK=Specifications]
Specifications and Features
Taken directly from their site
ST-750Z-AF Feature
â— ATX 12V V2.2 version compatible
â— Output Capacity: 750Watts Continuous
â— Advanced Cable Management System: Modularized cable design
â— Dual +12V rails for newest system: Maximum output current 60A
â— Standard compatibility: Support Intel Quad Core and AMD Dual Core CPU
Support Nvidia SLI VGA Card
â— Build in STNC fan control
â— 100% Hi-Pot test
â— Active PFC
â— High Efficiency>80%
â— Build in Japanese Capacitor
â— The Doubles Forward design structure
â— Big heat sink thickness the 5mm
â— 135mm Low-Noise Fan
â— Dimension: 163* 150 *86mm
â— Life expectancy: MTBF >100,000 hours
â— Multiple Protections Function
OCPã€OVPã€UVPã€OPP)
â— Safety Approvals:CE, TUV, CB, FCC, CUL and BSMI
â— 80PLUS Bronze Certified
â— NVIDIA SLI Certified
Specs -
[BREAK=Packaging &Contents]
[BREAK=Packaging &Contents Continued]
Connectivity options explained with the help of a diagram.
Load ratings for the entire V-Force range. The 750Z-AF has 2 rails of +12V rated at 25A and 35A. Impressive!
I would like to mention here that Seventeam underrates their units,at least I feel so. The reason I say so is because I happen to have their ST-600EAD unit for a few years now and it has easily handled whatever we could throw at it without a single complaint/breakdown. Initially we were a bit apprehensive about the 2 Year warranty but the 600EAD has never failed us.
Taking into consideration the stellar performance of our ST-600EAD unit, we had some high expectations from this 750W unit.
The PSU is secularly packed in styrofoam which prevents any damage during transit.
The package contains the PSU, cables, manual and power cord and a glitzy black velvet bag for keeping the extra cables which won’t be needed.
The sticker on the PSU gives detailed specs of the unit.
Total 60A on the +12V rails is impressive, hints us that this unit would be a very good performer.
Looking at the logo I was reminded of the first time I was told about this brand by an old TE’ite a few years back. Unfortunately he isn't active here anymore :no:
The huge 135mm fan does the duty of cooling the unit efficiently and quietly.
Notice these vents on the sides. Helps in better ventilation and hence keeps the components cooler, ensuring in better efficiency from the unit.
Like most computer and electronic components, even this unit has been made in china but thats ok. As long as its made as per Seventeam's specs and standards with the same quality control, it hardly matters where it is made.
A grill is provided at the rear of the PSU to facilitate better ventilation and hence cooling. Although this could be a cause of concern considering the dusty conditions we have here in India. Regular dusting with a blower should take care of that though. Not a major issue I think.
Power rocker switch is provided at the rear just like many other good quality PSUs. This is useful for quickly switching off the power to the PC. You don’t need to switch off the power from mains for that.
Modular connections are clearly demarcated for various components. This makes it easier to connect various components because different components have different power requirements. For example, HDD's draw far less power compared to a Graphic card. Now we don't know how the internal designing or load distribution on each rail. We wouldn't want to put a heavier load like that of a Graphic card on a rail which is not designed to handle such loads. This would cause the PSU to go bust.
We don't think so much in detail but these small things do help a lot and makes things simpler for us while building a system.
The quality of the unit is exceptional. The wires used are also of very high quality and gauge. By far this unit has to be amongst the best built unit we have come across. It may have some drawbacks in some other areas but when it comes to build quality, we were thoroughly impressed.
The ST-600EAD that we have had only the main ATX power cable sleeved but this unit comes with all the cables sleeved. This helps a lot in cable management. Although not a necessity, it is definitely a very useful feature that most good quality PSUs have these days.
This unit comes with a manual which can be useful for users who are not used to using modular units or high end PSUs and how they should be used.
[BREAK=Test setup and Testing methodology]
Test Setup
Intel Xeon W3570 @ 4.3GHz (HT on)
EVGA Classified e760 X58 Motherboard
XFX nVidia GeForce 295 GTX 1792MB DDR3
6GB 1600MHz CL8 A-Data DDR3 RAM
4 x Seagate SATA HDD's
1 x SATA DVDRW
8 x High CFM 120mm fans (10.8W each)
Thermalright Ultra 120 Extreme
Windows 7 Ultimate x64
These were the most power hungry components we could get together for testing this PSU
PSUs used while testing (for comparison) -
Seventeam ST-600EAD
Corsair HX620W
Corsair HX1000W
Testing methodology
Voltage readings were taken at idle (no load) and for load, Prime 95 + RTHDRIBL were run together and then 3DMark Vantage was ran twice to complete the load testing.
Voltage readings were taken with the help of multimeters from the molex connector, 24pin and PCIe power connectors and later through software in windows to check how accurate the readings from the software were.
[BREAK=Test results]
[BREAK=Conclusion]
Conclusion
When we started reviewing this PSU, we already had high expectations from it considering our earlier experience of using a Seventeam PSU and we are glad that we were not disappointed. Right from the build quality to the rock solid performance, everything about this PSU was impressive.
With the kind of performance it showcased, we can easily recommend this PSU to all those who are thinking of upgrading their PSUs or buying one for their new system. This PSU will suffice even if you have couple of hard drives along with 2 Graphic cards in SLI or Crossfire and a Core i7 to run the show.
Pros - Excellent Build Quality, Rock solid performance, quiet, long cables
Cons - Only 2 PCIe power connectors! Users with cards other than the 295 will need to use the molex to PCIe power converters.
Ratings –
Features – 9/10
Performance – 9/10
Value for Money – 10/10 (We have considered the units price listed on Newegg since currently this unit isn't available in India. So based on US pricing, we feel the Indian pricing would be ~ 1.5-2k more which makes the overall price 7,000-7,500/- approximately.)
Overall – 9.3/10
We would like to thank Seventeam for arranging this test sample.
Few years back, the concept of a standalone, high performance PSU was unknown to many here. It was only after high end hardware like Quad core CPUs, high end graphic cards, SLI, Crossfire, Dual GPU single slot cards started making an appearance that people realized the need of a good quality PSU.
Conventionally, PSUs would be bundled with the chassis and usually they would be rated at 300W or 400W which people thought would suffice and it did to some extent.
In reality these crappy bundled PSUs could hardly deliver even 180W of real power. This was exposed when people bought high end setups and their PSUs just couldn't handle their setups.
First it was the local chassis brands that started introducing high end PSUs which were rated at 500/600W. Although they were slightly better than the bundled ones, it was still a long way to go before we saw any REAL high end ones.
Sometime later, Antec entered the Indian market and that opened up the option for buyers to spend their hard earned money for buying good quality power supplies.
Later on many known brands like Coolermaster, Tagan, and Corsair etc. entered the Indian market.
Many of you may not be aware of a Taiwanese company called ‘Seventeam’ who are known to make some top quality PSUs for quite some time now.
What we have with us today is a PSU from Seventeam, the ST-750Z-AF which is a Modular PSU rated at 750W.
Before proceeding with this review, some information about Seventeam,
‘Seventeam Electronics was founded in 1986. Its headquarters and R&D center are based in Taipei,Taiwan and currently has instant sale and logistics network in major countries around the world.
Seventeam Electronics is the leading company in switching power supply products. Its leading expertise also dominates the markets in developing high performance, high watts, high stability and environmental products. It promotes the technology that is quiet and energy smart, furthermore, it tried hard to promote the concept of Semi-Fanless innovation. These features of the company are undoubtedly the strong forces in driving computer user experiences and the industry itself forward in the age that emphasizes computer speed.
The power supply products we offer include the power supply for PC and customized power supply for IPC (for industrial and server uses). We dedicate ourselves in promoting the global sale and service network of all Seventeam’s products. Our products are used by various global leading partners in system integration and we also offer multi-faceted OEM.ODM services’
Now that you are familiar with what Seventeam is and what we are going to review today, lets proceed on with the actual review

[BREAK=Specifications]
Specifications and Features
Taken directly from their site
ST-750Z-AF Feature
â— ATX 12V V2.2 version compatible
â— Output Capacity: 750Watts Continuous
â— Advanced Cable Management System: Modularized cable design
â— Dual +12V rails for newest system: Maximum output current 60A
â— Standard compatibility: Support Intel Quad Core and AMD Dual Core CPU
Support Nvidia SLI VGA Card
â— Build in STNC fan control
â— 100% Hi-Pot test
â— Active PFC
â— High Efficiency>80%
â— Build in Japanese Capacitor
â— The Doubles Forward design structure
â— Big heat sink thickness the 5mm
â— 135mm Low-Noise Fan
â— Dimension: 163* 150 *86mm
â— Life expectancy: MTBF >100,000 hours
â— Multiple Protections Function

â— Safety Approvals:CE, TUV, CB, FCC, CUL and BSMI
â— 80PLUS Bronze Certified
â— NVIDIA SLI Certified
Specs -

[BREAK=Packaging &Contents]
Packaging &Contents
Z-AF series is the Modular series while the P-AF is the normal one
This PSU belongs to Seventeam’s V-Force Series which is I think targeted more at enthusiasts and desktop users. The reason I say this is because Seventeam was always known for making PSUs for the Server market and not for normal desktop users like us. It seems now they are catering specially to enthusiasts and desktop users who need all the extra bling features like sleeving, modular connections etc.
This image shows you the saving in KWh per year achieved due to the >80% efficiency








Z-AF series is the Modular series while the P-AF is the normal one

This PSU belongs to Seventeam’s V-Force Series which is I think targeted more at enthusiasts and desktop users. The reason I say this is because Seventeam was always known for making PSUs for the Server market and not for normal desktop users like us. It seems now they are catering specially to enthusiasts and desktop users who need all the extra bling features like sleeving, modular connections etc.




This image shows you the saving in KWh per year achieved due to the >80% efficiency
[BREAK=Packaging &Contents Continued]

Connectivity options explained with the help of a diagram.

Load ratings for the entire V-Force range. The 750Z-AF has 2 rails of +12V rated at 25A and 35A. Impressive!
I would like to mention here that Seventeam underrates their units,at least I feel so. The reason I say so is because I happen to have their ST-600EAD unit for a few years now and it has easily handled whatever we could throw at it without a single complaint/breakdown. Initially we were a bit apprehensive about the 2 Year warranty but the 600EAD has never failed us.
Taking into consideration the stellar performance of our ST-600EAD unit, we had some high expectations from this 750W unit.



The PSU is secularly packed in styrofoam which prevents any damage during transit.

The package contains the PSU, cables, manual and power cord and a glitzy black velvet bag for keeping the extra cables which won’t be needed.

The sticker on the PSU gives detailed specs of the unit.


Total 60A on the +12V rails is impressive, hints us that this unit would be a very good performer.

Looking at the logo I was reminded of the first time I was told about this brand by an old TE’ite a few years back. Unfortunately he isn't active here anymore :no:

The huge 135mm fan does the duty of cooling the unit efficiently and quietly.

Notice these vents on the sides. Helps in better ventilation and hence keeps the components cooler, ensuring in better efficiency from the unit.


Like most computer and electronic components, even this unit has been made in china but thats ok. As long as its made as per Seventeam's specs and standards with the same quality control, it hardly matters where it is made.

A grill is provided at the rear of the PSU to facilitate better ventilation and hence cooling. Although this could be a cause of concern considering the dusty conditions we have here in India. Regular dusting with a blower should take care of that though. Not a major issue I think.

Power rocker switch is provided at the rear just like many other good quality PSUs. This is useful for quickly switching off the power to the PC. You don’t need to switch off the power from mains for that.

Modular connections are clearly demarcated for various components. This makes it easier to connect various components because different components have different power requirements. For example, HDD's draw far less power compared to a Graphic card. Now we don't know how the internal designing or load distribution on each rail. We wouldn't want to put a heavier load like that of a Graphic card on a rail which is not designed to handle such loads. This would cause the PSU to go bust.
We don't think so much in detail but these small things do help a lot and makes things simpler for us while building a system.


The quality of the unit is exceptional. The wires used are also of very high quality and gauge. By far this unit has to be amongst the best built unit we have come across. It may have some drawbacks in some other areas but when it comes to build quality, we were thoroughly impressed.




The ST-600EAD that we have had only the main ATX power cable sleeved but this unit comes with all the cables sleeved. This helps a lot in cable management. Although not a necessity, it is definitely a very useful feature that most good quality PSUs have these days.

This unit comes with a manual which can be useful for users who are not used to using modular units or high end PSUs and how they should be used.

Test Setup
Intel Xeon W3570 @ 4.3GHz (HT on)
EVGA Classified e760 X58 Motherboard
XFX nVidia GeForce 295 GTX 1792MB DDR3
6GB 1600MHz CL8 A-Data DDR3 RAM
4 x Seagate SATA HDD's
1 x SATA DVDRW
8 x High CFM 120mm fans (10.8W each)
Thermalright Ultra 120 Extreme
Windows 7 Ultimate x64
These were the most power hungry components we could get together for testing this PSU
PSUs used while testing (for comparison) -
Seventeam ST-600EAD
Corsair HX620W
Corsair HX1000W
Testing methodology
Voltage readings were taken at idle (no load) and for load, Prime 95 + RTHDRIBL were run together and then 3DMark Vantage was ran twice to complete the load testing.
Voltage readings were taken with the help of multimeters from the molex connector, 24pin and PCIe power connectors and later through software in windows to check how accurate the readings from the software were.
[BREAK=Test results]
Test results
Here we see that the ST-600 unit is struggling slightly when under load but it’s within the ATX standards.
The HX620W too does fluctuate a bit but it’s within limits. The HX1000 and the 750Z-AF have no problem delivering the same steady power even under load as expected.
All the PSUs handled the +5v load pretty well. Most of the storage devices like HDD’s, ODD’s and USB devices use this rail so it’s just as important as the +12v rail
Very few devices use this rail aside from SATA power connectors so all PSU’s do well here as well.
We decided to measure the lengths of the cables for each unit since it is quite crucial sometimes while deciding which case to go for. Few cases have the PSU placement at the bottom and that can cause problems especially for the EPS 8Pin connector which is farthest from the PSU.
We were pleased to notice that the 750Z-AF had the longest cables of all of the PSU’s we’ve ever used to date, especially the SATA and Molex cables. Sometimes the HDD cage is far away from the PSU so longer cables always help.
We were shocked to see that the HX1000 has shorter SATA and Molex cables even compared to the HX620? We don’t see a reason as to why this is the case!
For the Power consumption test, we used the same setup and the tests were also run in the exact same manner to maintain the uniformity for fair competition.
The ST-600EAD drew the least power when at idle whereas the HX1000 draws the most power.
Under load, the situation changes a bit, the least power drawn is from the HX620 and the maximum is from HX1000 which could be because its efficiency is directly proportional to the load.
The 750Z-AF drew 304W when at idle and 534W under load which is good enough considering the figures of the other competing PSUs.
Lastly we also took software readings through Lavalys Everest Ultimate Edition 5.30 and HWMonitor 1.15 to compare to the readings taken by the multimeter to check how accurate the software readings were.
The software readings are quite accurate compared to the Multimeter readings.Although the readings might be slightly off compared to the Multimeter readings but the overall picture is the same.
The 600EAD struggles under load whereas the remaining three are pretty steady and handle the load easily.

Here we see that the ST-600 unit is struggling slightly when under load but it’s within the ATX standards.
The HX620W too does fluctuate a bit but it’s within limits. The HX1000 and the 750Z-AF have no problem delivering the same steady power even under load as expected.

All the PSUs handled the +5v load pretty well. Most of the storage devices like HDD’s, ODD’s and USB devices use this rail so it’s just as important as the +12v rail

Very few devices use this rail aside from SATA power connectors so all PSU’s do well here as well.
We decided to measure the lengths of the cables for each unit since it is quite crucial sometimes while deciding which case to go for. Few cases have the PSU placement at the bottom and that can cause problems especially for the EPS 8Pin connector which is farthest from the PSU.
We were pleased to notice that the 750Z-AF had the longest cables of all of the PSU’s we’ve ever used to date, especially the SATA and Molex cables. Sometimes the HDD cage is far away from the PSU so longer cables always help.
We were shocked to see that the HX1000 has shorter SATA and Molex cables even compared to the HX620? We don’t see a reason as to why this is the case!

For the Power consumption test, we used the same setup and the tests were also run in the exact same manner to maintain the uniformity for fair competition.
The ST-600EAD drew the least power when at idle whereas the HX1000 draws the most power.
Under load, the situation changes a bit, the least power drawn is from the HX620 and the maximum is from HX1000 which could be because its efficiency is directly proportional to the load.
The 750Z-AF drew 304W when at idle and 534W under load which is good enough considering the figures of the other competing PSUs.

Lastly we also took software readings through Lavalys Everest Ultimate Edition 5.30 and HWMonitor 1.15 to compare to the readings taken by the multimeter to check how accurate the software readings were.


The software readings are quite accurate compared to the Multimeter readings.Although the readings might be slightly off compared to the Multimeter readings but the overall picture is the same.
The 600EAD struggles under load whereas the remaining three are pretty steady and handle the load easily.
[BREAK=Conclusion]
Conclusion
When we started reviewing this PSU, we already had high expectations from it considering our earlier experience of using a Seventeam PSU and we are glad that we were not disappointed. Right from the build quality to the rock solid performance, everything about this PSU was impressive.
With the kind of performance it showcased, we can easily recommend this PSU to all those who are thinking of upgrading their PSUs or buying one for their new system. This PSU will suffice even if you have couple of hard drives along with 2 Graphic cards in SLI or Crossfire and a Core i7 to run the show.
Pros - Excellent Build Quality, Rock solid performance, quiet, long cables
Cons - Only 2 PCIe power connectors! Users with cards other than the 295 will need to use the molex to PCIe power converters.
Ratings –
Features – 9/10
Performance – 9/10
Value for Money – 10/10 (We have considered the units price listed on Newegg since currently this unit isn't available in India. So based on US pricing, we feel the Indian pricing would be ~ 1.5-2k more which makes the overall price 7,000-7,500/- approximately.)
Overall – 9.3/10


We would like to thank Seventeam for arranging this test sample.