Introduction

We’ve already tested the 450 W version from power supply series from 3R System, and it proved to be a product with an excellent cost/benefit ratio. Now let’s see if the 500 W version is also a good buy.

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Figure 1: 3R System iCEAGE IA500HP80 power supply.

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Figure 2: 3R System iCEAGE IA500HP80 power supply.

3R System iCEAGE IA500HP80 is 6 1/8” (15.5 cm) deep, using a 140 mm fan on its bottom. This unit does not feature a PFC circuit, as you can see by the presence of a 115 V/230 V switch in Figure 1. This power supply is also available as a 230 V only product. Although it does not have PFC, internally the unit uses a design that is more modern than the one used by low-cost power supplies, as we will explain later.

No modular cabling system is provided and all cables have nylon protections, that come from inside the power supply housing. The cables included are:

• Main motherboard cable with a 20/24-pin connector, 20 7/8” (53 cm) long.
• One cable with two ATX12V connectors that together form one EPS12V connector, 22 7/8” (58 cm) long.
• Two cables with one six/eight-pin connector for video cards each, 15 ¾” (40 cm) long.
• Two cables with three SATA power connectors each, 15 ¾” (40 cm) to the first connector, 5 7/8” (15 cm) between connectors).
• One cable with two standard peripheral power connectors, 15 ¾” (40 cm) to the first connector, 5 7/8” (15 cm) between connectors).
• One cable with two standard peripheral power connectors and one floppy disk drive power connector, 15 ¾” (40 cm) to the first connector, 5 7/8” (15 cm) between connectors).

This configuration is exactly the same cable configuration used on the 450 W model from this series, and we think it is good enough for an entry-level 500 W power supply. All cables use 18 AWG wires, which is the minimum recommended.

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Figure 3: Cables.

Now let’s take an in-depth look inside this power supply.

A Look Inside The 3R System iCEAGE IA500HP80

We decided to disassemble this power supply to see what it looks like inside, how it is designed, and what components are used. Please read our Anatomy of Switching Power Supplies tutorial to understand how a power supply works and to compare this power supply to others.

This page will be an overview, while in the following pages we will discuss the quality and ratings of the components used in detail. As you can see, the secondary heatsink has a heat pipe attached to it.

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Figure 4: Overall look.

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Figure 5: Overall look.

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Figure 6: Overall look.

Transient Filtering Stage

As we have mentioned in other articles and reviews, the first place we look when opening a power supply for a hint about its quality is its filtering stage. The recommended components for this stage are two ferrite coils, two ceramic capacitors (Y capacitors, usually blue), one metalized polyester capacitor (X capacitor), and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components, usually removing the MOV and the first coil.

Even though this power supply has one X capacitor more than the minimum required, it lacks an MOV, which is the component in charge of removing spikes coming from the power grid.

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Figure 7: Transient filtering stage (part 1).

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Figure 8: Transient filtering stage (part 2).

In the next page we will have a more detailed discussion of the components used in the 3R System iCEAGE IA500HP80.

Primary Analysis

On this page we will take an in-depth look at the primary stage of Nexus RX-6300. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.

This power supply uses one KBU1006 rectifying bridge, which supports up to 10 A at 65º C if a heatsink is used, which is not the case. At 115 V this unit would be able to pull up to 1,150 W from the power grid; assuming 80% efficiency, the bridge would allow this unit to deliver up to 920 W without burning itself. Of course we are only talking about this component and the real limit will depend on all other components from the power supply. The 450 W model uses an 8 A bridge here, so it is nice to see that the manufacturer really upgraded components on the 500 W version.

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Figure 9: Rectifying bridge.

Usually low-cost power supplies without PFC circuit are based on the obsolete half-bridge design, but like its 450 W sister iCEAGE IA500HP80 is based on a two-transistor forward design, which is the same design used by power supplies with active PFC. This is the first time we’ve seen a power supply series without PFC using this topology.

In the switching section, two STW25NM60N power MOSFET transistors are used on the two-transistor forward configuration, as mentioned. Each transistor is capable of handling up to 21 A at 25º C or up to 13 A at 100º C in continuous mode, or up to 84 A at 25º C in pulse mode. These transistors present a maximum RDS(on) of 160 mΩ. This number measures the resistance provided by the transistors when they are turned on; the lower this number, the better (higher efficiency). These transistors are more powerful than the ones used on the 450 W version.

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Figure 10: Switching transistors.

The switching transistors are controlled by a UC3843 PWM controller.

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Figure 11: PWM controller.

Now let’s take a look at the secondary of this power supply.

Secondary Analysis

This power supply has five Schottky rectifiers on its secondary.

The maximum theoretical current each line can deliver is given by the formula I / (1 - D), where D is the duty cycle used and I is the maximum current supported by the rectifying diode. Just as an exercise, we can assume a typical duty cycle of 30%.

The +12 V output is produced by two STPS30H100CT Schottky rectifiers, each one supporting up to 30 A (15 A per internal diode at 155º C, 0.93 V maximum voltage drop), giving us a maximum theoretical current of 43 A or 514 W for the +12 V output. These components were upgraded from the 450 W model, which uses two 20 A rectifiers here (maximum theoretical current of 29 A or 343 W).

The +5 V output is produced by two STPS30S45CW Schottky rectifiers, each one supporting up to 30 A (15 A per internal diode at 110º C, 0.57 V maximum voltage drop), giving us a maximum theoretical current of 43 A or 214 W for the +5 V output. These are exactly the same rectifiers used  on the 450 W model.

The +3.3 V output is produced by another STPS30S45CW Schottky rectifier, giving us a maximum theoretical current of 21 A or 71 W for the +3.3 V output. This is exactly the same rectifier used on the 450 W model.

All these numbers are theoretical. The real amount of current/power each output can deliver is limited by other components, especially by the coils used on each output.

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Figure 12: +3.3 V, +12 V and +5 V rectifiers.

The outputs are monitored by a WT751002 integrated circuit, which supports only OVP (over voltage protection) and UVP (under voltage protection). Any other protection this unit may have is implemented outside this chip.

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Figure 13: Monitoring integrated circuit.

The capacitors from the voltage doubler circuit are from a company called LCZ, while the capacitors on the secondary are from a company called BH.

Power Distribution

In Figure 14, you can see the power supply label containing all the power specs.

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Figure 14: Power supply label.

As you can see, according to the label this unit has two +12 V rails. However inside the power supply this product has only one +12 V rail and thus this unit is a single-rail unit. What happens is that 3R System added separated filtering circuits for the two group of wires they call +12V1 and +12V2, which is great, but what constitutes a two-rail design is the presence of two over current protection (OCP) circuits, which this power supply doesn’t have. Read our Everything You Need to Know About Power Supply Protections tutorial for more information.

Now let’s see if this power supply can really deliver 500 W.

Load Tests

We conducted several tests with this power supply, as described in the article Hardware Secrets Power Supply Test Methodology.  

First we tested this power supply with five different load patterns, trying to pull around 20%, 40%, 60%, 80%, and 100% of its labeled maximum capacity (actual percentage used listed under “% Max Load”), watching how the reviewed unit behaved under each load. In the table below we list the load patterns we used and the results for each load.

If you add all the power listed for each test, you may find a different value than what is posted under “Total” below. Since each output can vary slightly (e.g., the +5 V output working at 5.10 V), the actual total amount of power being delivered is slightly different than the calculated value. On the “Total” row we are using the real amount of power being delivered, as measured by our load tester.

The +12VA and +12VB inputs listed below are the two +12 V independent inputs from our load tester. During this test both inputs were connected to the power supply single rail (+12VB input was connected to the power supply EPS12V connector and all other cables were connected to the load tester +12VA input).

Input	Test 1	Test 2	Test 3	Test 4	Test 5
+12VA	4 A (48 W)	7 A (84 W)	11 A (132 W)	14.5 A (174 W)	17.5 A (210 W)
+12VB	3 A (36 W)	7 A (84 W)	10 A (120 W)	14 A (168 W)	17 A (204 W)
+5V	1 A (5 W)	2 A (10 W)	4 A (20 W)	6 A (30 W)	8 A (40 W)
+3.3 V	1 A (5 W)	2 A (6.6 W)	4 A (13.2 W)	6 A (19.8 W)	8 A (26.4 W)
+5VSB	1 A (5 W)	1 A (5 W)	1.5 A (7.5 W)	2 A (10 W)	2.5 A (12.5 W)
-12 V	0.5 A (6 W)	0.5 A (6 W)	0.5 A (6 W)	0.5 A (6 W)	0.5 A (6 W)
Total	102.2 W	193.4 W	294.7 W	399.7 W	492.6 W
% Max Load	20.4%	38.7%	58.9%	79.9%	98.5%
Room Temp.	43.1º C	42.6º C	43.2º C	44.9º C	47.5º C
PSU Temp.	41.9º C	42.8º C	43.5º C	44.8º C	46.8º C
Voltage Regulation	Pass	Pass	Pass	Pass	Pass
Ripple and Noise	Pass	Pass	Pass	Pass	Pass
AC Power	124.4 W	231.3 W	355.8 W	493.0 W	620.0 W
Efficiency	82.2%	83.6%	82.8%	81.1%	79.5%
AC Voltage	116.7 V	115.1 V	114.0 V	112.7 V	111.6 V
Power Factor	0.606	0.65	0.67	0.683	0.693
Final Result	Pass	Pass	Pass	Pass	Pass

iCEAGE IA500HP80 from 3R System can really deliver its labeled power at high temperatures.

This power supply presented a decent efficiency between 81.1% and 83.6% when we pulled up to 400 W from it. At its maximum capacity (500 W), efficiency dropped a little bit below 80%. This power supply and its 450 W sister are the only two power supplies without active PFC that we’ve seen to date achieving efficiency above 80%.

Voltage regulation was superb, with all voltages within 3% from their nominal values (including the -12 V output) – i.e., values closer to their “face value” than required, as the ATX12V specification allows voltages to be within 5% from their nominal values (10% for -12 V). The only exception was +5 V during test five, but it was still within the 5% tolerance.

And then we have noise and ripple, always very low, except on +3.3 V during test five, where this output was operating too close to its maximum allowed level (the same thing happened with the 450 W model, so this is a characteristic from this particular project). Below you can see the results for test five. The maximum allowed is 120 mV on +12 V and 50 mV on +5 V and +3.3 V. All these numbers are peak-to-peak figures.

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Figure 15: +12VA input from load tester at 492.6 W (28.8 mV).

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Figure 16: +12VB input from load tester at 492.6 W (33.4 mV).

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Figure 17: +5 V rail with power supply delivering 492.6 W (13.6 mV).

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Figure 18: +3.3 V rail with power supply delivering 492.6 W (46.2 mV).

Now let’s see if this unit can deliver more than 500 W.

Overload Tests

First we tried to see if over current protection (OCP) was active; we maxed out the power supply and the unit didn’t shut down.

Then we tried to pull the maximum we could with the power supply still operating under ATX12V specs. The results you can see below. At this test noise level at +3.3 V was already above the maximum allowed. We could pull even more power from this unit, but noise level at +12 V and +5 V would go also out of spec.

Input	Overload Test
+12V1	22 A (264 W)
+12V2	22 A (264 W)
+5V	10 A (50 W)
+3.3 V	10 A (33 W)
+5VSB	3 A (36 W)
-12 V	0.5 A (6 W)
Total	608.7 W
% Max Load	121.7%
Room Temp.	45.4º C
PSU Temp.	46.8º C
AC Power	800.0 W
Efficiency	76.1%
AC Voltage	109.7 V
Power Factor	0.707

Main Specifications

3R System iCEAGE IA500HP80 power supply specs include:

• ATX12V 2.3
• Nominal labeled power: 500 W.
• Measured maximum power: 608.7 W at 45.4º C.
• Labeled efficiency: 80%
• Measured efficiency: Between 79.5% and 83.6% at 115 V (nominal, see complete results for actual voltage).
• Active PFC: No.
• Modular Cabling System: No.
• Motherboard Power Connectors: One 20/24-pin connector and two ATX12V connectors that together form an EPS12V connector.
• Video Card Power Connectors: Two six/eight-pin connectors in separated cables.
• SATA Power Connectors: Six in two cables.
• Peripheral Power Connectors: Four in two cables.
• Floppy Disk Drive Power Connectors: One.
• Protections: Information not available.
• Warranty: Information not available.
• More Information: http://www.3rsys.com
• Average price in the US: This product is not sold in the USA.

Conclusions

Like the 450 W version, 3R System iCEAGE IA500HP80 surprised us. Although being clearly a low-cost power supply, it could achieve efficiency above 80% when we pulled up to 400 W (peaking 83.6%). At full load (500 W) efficiency was at 79.5%. These are fantastic results for a power supply without 80 Plus certification. These 450 W and 500 W power supplies from 3R System are the only units without PFC circuit that we’ve seen achieving such performance – which was possible thanks to the use of a two-transistor forward switching circuit, and also these are the only two power supplies without PFC circuit we’ve seen using this modern design.

Voltage regulation was superb, with all voltages within 3% from their nominal values (including the -12 V output) – i.e., values closer to their “face value” than required, as the ATX12V specification allows voltages to be within 5% from their nominal values (10% for -12 V). The only exception was +5 V when we pulled 500 W from it, which was still within the required 5% tolerance.

Noise and ripple were always very low, except at +3.3 V when we pulled the full 500 W from this unit – something that also happened with the 450 W model, so this is a particular characteristic from the project used. This is the only reason we are giving it our Silver Award instead of Golden.

Although the 450 W and 500 W units are based on the same project, 3R System upgraded the rectifying bridge, the switching transistors and the +12 V rectifiers on the 500 W. This is the correct approach. Usually on low-cost power supplies the manufacturer only upgrades the +5 V rectifier, which doesn’t make any sense at all nowadays, since most power is pulled from +12 V (because that is where the CPU and the video cards are connected to).

For the user on budget living in a country where this power supply is available, this unit is a terrific option, presenting a terrific performance for its price.