Review of the Zalman ZM500-RS PSU

Summary: Zalman ZM500-RS is the company’s most recently released power supply unit and promises a high power conversion efficiency (80 plus bronze) in combination with a minimal noise level.


ZM500-RS


INTRODUCTION

The new series of power supplies recently released by Zalman ha a “RS” suffix in its name which stands for “Resonant Switching”. Compared to Two-Forward Switching, the more advanced Resonant Switching minimizes “switching loss” reduces heat generation, and operates more efficiently by eliminating the need for an output inductor leading to outstanding stability and reliability.

003735


{openix:146}


With the use of “Resonant Switching” it is possible to use smaller components which don’t generate as much heat. Thus, it’s possible to use o less noisy cooling solution. As the RS technology minimizes the loss of power in the conversion, this can be considered a very “green” and energy saving product.


003736


OK, so let’s have a look at the specifications:


Zalman ZM500-RS

Power

500W

Efficiency

87% maximum. “80+BRONZE”

Fixed wiring

ATX 20+4 pin connector
6 PCI-E pin connector
6+2 PCI-E pin connector
4+4 ATX 12V pin connector
4 SATA connectors
4 molex connectors
1 FDD connector

PFC

99% maximum

Cooling solution

120mm fan

Electrical protections

OVP, OCP, SCP, OTP, UVP

Dimensions

140 x 150 x 86 mm

Power in

100V/240V  
8A/4A 
50/60Hz

Power out

+3.3V

24A (tip of 30A)

+5V

24A (tip of 30A)

+12V1

18A (tip of 22A)

+12V2

18A (tip of 22A)

-12V

0,5A

+5VSB

3A (tip of 3,5A)

Combined power maximum

+3.3V, +5V

130W

+12V

432W

-12V, +5VSB

21W

+3.3V, +5V, +12V, +5VSB

500W


The RS-series also includes a 600W model perhaps more adapted to high end components. The RS-series will without a doubt be very appreciated by builders of compact systems, the only thing I miss is a modular design for the wiring.




FIRST IMPRESSIONS

The unit comes in a nice looking cardboard box with a lot of printing on it which emphasizes the most important characteristics of the power supply.


003715 003716
003717 003718


In the back side of the box, Zalman has put some images of details such as the wiring and used components. They have also placed summaries in different languages of the most important specifications.


003719 003720


In the box I found the power supply (perfectly protected); a power cable; some plastic bridles; screws and the manual.


003721



ZALMAN ZM500-RS IN DETAIL

One of the first things that I noticed about the Zalman ZM500-RS is that it’s smaller than normal PSUs. Of course it still follows the ATX standard in terms of where the screws are placed and everything else. It’s just not as bulky as what I am used to, which makes it ideal for smaller dimensions cases.


003722 003723


The side with the power cord connector and the on/off switch has a metallic grid to increase the air flow. The right side has the Zalman logo engraved in it. The opposite side holds a big tag with all the specifications of the power supply.


003724 003725


003726 003727


The cooling solution consists of a 120mm fan which runs at a constant speed (not heat regulated). Of course I had to take the top cover off and take a look. I found out that this PSU is actually assembled by POWER LOGIC which is a well know builder of PSUs, used by other players like Xigmatek and Asus.


003731 003732


003733 003734



{openix:146}


The wiring of the Zalman ZM500-RS is contained by strong acrylic plastic which holds it firmly in place. The length of the wiring is sufficient for an average tower case but I wouldn’t recommend using it with full tower cases.


003739


003728 003729



TESTS OF ZALMAN ZM500-RS

This will be one of the last reviews I do with my usual test system setup, never the less, here are the specifications:


Test equipment

Processor

AMD Phenom II 920

Fan

Cooler Master Hyper N520

Motherboard

Sapphire PC-AM2RD790 – CrossFireX PUREE

Graphics card

Sapphire Radeon HD 2900XT

Soundcard

Auzen X-Fi Forte 7.1

Memory

Kingston HyperX DDR2 1066 2x2GB T1 Series

Hard disk

Samsung SP2504C (SATA II, 7200rmp, 8MB)

Power supply

Zalman ZM500-RS

Case

Antec Skeleton



To realize the test I used OCCT 3.1 to load the system to the max. In order to measure the voltages I used an ordinary digital multimeter and the power usage was measured with the ZM-MFC3 which I reviewed last week. The results can be viewed in the graph below:


003740


003741


As you can see from the graphs, the numbers the Zalman ZM500-RS produced are excellent. The voltages are tremendously stable; the PSU remains totally capable of delivering the power as it should even at full system load. The total consumption at full system load is the lowest I have measured with my system, which surely is a result of the Resonant Switching technology.


003737 003738


The noise emitted by this PSU is almost not possible to hear, that is just how quiet the fan is and because the fan turns at a constant speed the load doesn’t affect the noise emission.




CONCLUSIONS

Doubtless the Zalman ZM500-RS is a high quality power supply with many interesting characteristics. I love that it’s small which makes it perfect to put in a small HTPC case or any other smaller PC case. However, the wiring is rather short so if you are building a PC system in a full tower case you will probably not be able to use this PSU without any extension cables.


{openix:146}


The performance is absolutely fantastic, it is in fact the most energy efficient PSU I have tested so far. The energy efficiency is of ever increasing importance and it’s nice to know that your system is using up the minimum amount of power, which will in the end mean minimal cost. The PSU is ultra quiet and the voltages are stable no matter what you throw at it.


Zalman has done a great work with this product; the RS technology is a smart innovation that will save you money in the long run. The price of the ZM500-RS goes up to around 90€ which is a lot of money for a PSU. It is clearly aimed towards PC builders with a bigger budget or anyone interested in its power saving or low noise features.


Good:

  • Overall quality
  • Size, ideal for smaller dimension cases
  • Energy saving technologies
  • Stability and efficiency
  • Very quiet cooling solution


Bad:

  • Modular wiring would have been nice
  • Short wires could cause problems


Zalman ZM500-RS

Packing and accessories

0.25/0.5

Quality and finished

1/1

Wiring

1/1,5

Loudness

2.5/2.5

Performance

2.5/2.5

Price

1.25/2

Total

9/10


The final score is 90 out of 100 owls, and we give the “Zalman ZM500-RS″ our Editor’s Choice Award.




TestSeek Labs Editor's Choice 2009 Award

 

 

 

Thanks goes out to Zalman for letting me review this PSU.



Author: Manuel González Fernández

Translator: Vince Emiloz Sanderson


  1. No comments yet.
  1. No trackbacks yet.
You must be logged in to post a comment.