Introduction

The Basiq power supply series from Antec is targeted to users with serious budget restrictions. The new VP350 and VP450 models are the most entry-level power supplies offered by Antec, as they don’t have a PFC circuit or 80 Plus certification. Let’s see whether the 450 W model, which is sold for only USD 40, is worth considering.

The VP450 model is manufactured by FSP, while the VP350 is manufactured by Delta. Therefore, they are based on different designs.

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Figure 1: Antec VP450 power supply

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Figure 2: Antec VP450 power supply

The Antec VP450 is 5.5” (140 mm) deep, using a 120 mm sleeve bearing fan on its bottom (Yate Loon D12SH-12).

This unit doesn’t have a modular cabling system, and only the main motherboard cable uses a nylon sleeve, which comes from inside the unit. This power supply comes with the following cables:

• Main motherboard cable with a 20/24-pin connector, 18.1” (46 cm) long
• One cable with two ATX12V connectors that together form an EPS12V connector, 20.1” (51 cm) long
• One cable with one six-pin connector for video cards, 18.1” (46 cm) long
• One cable with three SATA power connectors, 17.3” (44 cm) to the first connector, 5.9” (15 cm) between connectors
• One cable with one SATA power connector, one standard peripheral power connector and one floppy disk drive power connector, 17.3” (44 cm) to the first connector, 5.9” (15 cm) between connectors
• One cable with two standard peripheral power connectors and one floppy disk drive power connector, 17.3” (44 cm) to the first connector, 5.9” (15 cm) between connectors

All wires are 18 AWG wires, which is the minimum recommended gauge.

The cable configuration is excellent for a budget 450 W power supply.

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Figure 3: Cables

Let’s now take an in-depth look inside this power supply.

A Look Inside the Antec VP450

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.

On this page we will have an overall look, and then in the following pages we will discuss in detail the quality and ratings of the components used.

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Figure 4: Top view

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Figure 5: Front quarter view

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Figure 6: Rear quarter view

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Figure 7: The printed circuit board

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. 

The Antec VP450 has two Y capacitors and one X capacitor more than the minimum required. The MOVs are located in parallel with the electrolytic capacitors from the voltage doubler circuit.

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Figure 8: Transient filtering stage (part 1)

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Figure 9: Transient filtering stage (part 2)

On the next page, we will have a more detailed discussion about the components used in the Antec VP450.

Primary Analysis

On this page we will take an in-depth look at the primary stage of the Antec VP450. For a better understanding, please read our “Anatomy of Switching Power Supplies” tutorial.

This power supply uses one GBU1006 rectifying bridge, which is attached to an individual heatsink. This bridge supports up to 10 A at 100° C, so in theory, you would be able to pull up to 1,150 W from a 115 V power grid. Assuming 80% efficiency, the bridge would allow this unit to deliver up to 920 W without burning itself out. Of course, we are only talking about this particular component. The real limit will depend on all the components combined in this power supply.

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Figure 10: Rectifying bridge

As mentioned before, this power supply doesn’t have a PFC circuit.

The voltage doubler circuit uses two 820 µF x 200 V electrolytic capacitors from Teapo and labeled at 85° C.

Usually, power supplies without a PFC circuit are based on the obsolete half-bridge design; the Antec VP450 uses the two-transistor forward configuration, which is great.

In the switching section, two JCS18N50FH MOSFETs are used in the traditional two-transistor forward configuration, supporting up to 18 A at 25° C or 11 A at 100° C in continuous mode, or up to 72 A at 25° C in pulse mode, with an RDS(on) of 270 mΩ.

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Figure 11: The switching transistors

The switching transistors are controlled by a UC3845B PWM controller.

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Figure 12: PWM controller

Let’s now take a look at the secondary of this power supply.

Secondary Analysis

The Antec VP450 uses a regular design in its secondary, with Schottky rectifiers.

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. As an exercise, we can assume a duty cycle of 30 percent.

The +12 V output uses two MBR20100CT Schottky rectifiers (20 A, 10 A per internal diode at 120° C, 0.95 V maximum voltage drop). This gives us a maximum theoretical current of 29 A or 343 W for the +12 V output.

The +5 V output uses one HBR3045 Schottky rectifier (30 A, 15 A per internal diode at 150° C, 0.7 V maximum voltage drop). This gives us a maximum theoretical current of 21 A or 107 W for the +5 V output.

The +3.3 V output uses another HBR3045 Schottky rectifier. This gives us a maximum theoretical current of 21 A or 71 W for the +3.3 V output.

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Figure 13: The +3.3 V, +12 V, and +5 V rectifiers

This power supply uses a WT7527 monitoring integrated circuit, which supports over voltage (OVP), under voltage (UVP), and over current (OCP) protections. This chip offers two +12 V channels, correctly matching the number of +12 V rails advertised by the manufacturer.

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Figure 14: Monitoring circuit

The electrolytic capacitors that filter the outputs are from CapXon and Teapo, and labeled at 105° C, as usual.

Power Distribution

In Figure 15, you can see the power supply label containing all the power specs.

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Figure 15: Power supply label

As you can see, this power supply is sold as having two +12 V rails, which is correct, since this unit has two +12 V over current protection circuits (see previous page), and we could clearly see two “shunts” (current sensors). See Figure 16. Click here to understand more about this subject.

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Figure 16: Shunts

The two +12 V rails are distributed as follows:

• +12V1: All cables but the EPS12V/ATX12V
• +12V2: The EPS12V/ATX12V cable

This is the typical distribution used by power supplies with two +12 V virtual rails.

How much power can this unit really deliver? Let’s find out.

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 the behavior of the reviewed unit 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 powers listed for each test, you may find a different value than what is posted under “Total” below. Since each output can have a slight variation (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. In 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, the +12VA input was connected to the power supply +12V1 rail, while the +12VB input was connected to the power supply +12V2 rail.

Input	Test 1	Test 2	Test 3	Test 4	Test 5
+12VA	3 A (36 W)	6 A (72 W)	9 A (108 W)	12 A (144 W)	15.5 A (186 W)
+12VB	3 A (36 W)	6 A (72 W)	9 A (108 W)	12 A (144 W)	15.5 A (186 W)
+5 V	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 (3.3 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 A (5 W)	1.5 A (7.5 W)	2 A (10 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	90.5 W	166.8 W	258.1 W	338.8 W	448.9 W
% Max Load	20.1%	37.1%	57.4%	75.3%	99.8%
Room Temp.	45.3° C	44.6° C	44.8° C	44.2° C	45.6° C
PSU Temp.	47.4° C	46.6° C	46.1° C	46.2° C	47.2° C
Voltage Regulation	Pass	Pass	Pass	Pass	Pass
Ripple and Noise	Pass	Pass	Pass	Pass	Pass
AC Power	108.4 W	195.2 W	305.3 W	407.7 W	559.0 W
Efficiency	83.5%	85.5%	84.5%	83.1%	80.3%
AC Voltage	120.3 V	119.1 V	118.0 V	116.7 V	115.4 V
Power Factor	0.587	0.637	0.670	0.683	0.698
Final Result	Pass	Pass	Pass	Pass	Pass

The Antec VP450 passed our tests with flying colors.

Efficiency was between 80.3% and 85.5% during our tests, which is outstanding for a budget power supply. The only reason this unit can’t get the 80 Plus certification is that only power supplies with a PFC circuit can be certified, as the 80 Plus certification requires a power factor of at least 0.900 at full load.

Voltage regulation was outstanding, with all voltages closer to their nominal values than required (three percent regulation), except for the -12 V output, which was still inside the allowed range. The ATX12V specification states that positive voltages must be within 5% of their nominal values, and negative voltages must be within 10% of their nominal values.

Let’s discuss the ripple and noise levels on the next page.

Ripple and Noise Tests

Voltages at the power supply outputs must be as “clean” as possible, with no noise or oscillation (also known as “ripple”). The maximum ripple and noise levels allowed are 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V, +3.3 V and +5VSB outputs. All values are peak-to-peak figures. We consider a power supply as being top-notch if it can produce half or less of the maximum allowed ripple and noise levels.

The Antec VP450 provided ripple and noise levels within specs, as you can see in the table below.

Input	Test 1	Test 2	Test 3	Test 4	Test 5
+12VA	43.4 mV	34.2 mV	51.2 mV	60.6 mV	74.8 mV
+12VB	48.2 mV	37.2 mV	55.2 mV	65.2 mV	79.6 mV
+5 V	21.8 mV	14.4 mV	20.4 mV	20.4 mV	21.6 mV
+3.3 V	16.8 mV	10.8 mV	18.6 mV	17.8 mV	19.2 mV
+5VSB	22.6 mV	15.2 mV	23.6 mV	23.8 mV	34.8 mV
-12 V	33.8 mV	24.4 mV	42.2 mV	47.0 mV	56.4 mV

Below you can see the waveforms of the outputs during test five.

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Figure 17: +12VA input from load tester during test five at 448.9 W (74.8 mV)

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Figure 18: +12VB input from load tester during test five at 448.9 W (79.6 mV)

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Figure 19: +5V rail during test five at 448.9 W (21.6 mV)

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Figure 20: +3.3 V rail during test five at 448.9 W (19.2 mV)

Let’s see if we can pull more than 450 W from this unit.

Overload Tests

Below you can see the maximum we could pull from this power supply. The objective of this test is to see if the power supply has its protection circuits working properly. This unit passed this test, as we couldn’t pull more than shown in the table below, as the power supply would shut down, showing that its protections are present and working fine. During this extreme configuration, noise and ripple levels and voltages were still inside the proper limits.

Input	Overload Test
+12VA	22 A (264 W)
+12VB	22 A (264 W)
+5 V	8 A (40 W)
+3.3 V	8 A (26.4 W)
+5VSB	3 A (15 W)
-12 V	0.5 A (6 W)
Total	553.6 W
% Max Load	123.0%
Room Temp.	46.7° C
PSU Temp.	48.5° C
AC Power	731.0 W
Efficiency	75.7%
AC Voltage	113.5 V
Power Factor	0.712

Main Specifications

The main specifications for the Antec VP450 power supply include:

• Standards: ATX12V 2.3
• Nominal labeled power: 450 W
• Measured maximum power: 553.6 W at 46.7° C
• Labeled efficiency: NA
• Measured efficiency: Between 80.3% and 85.5% 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: One six-pin connector
• SATA Power Connectors: Four on two cables
• Peripheral Power Connectors: Three on two cables
• Floppy Disk Drive Power Connectors: Two on two cables
• Protections (as listed by the manufacturer): Over current (OCP), over voltage (OVP), over power (OPP), and short circuit (SCP)
• Are the above protections really available? Yes. This unit also has under voltage protection (UVP).
• Warranty: Two years
• Real Manufacturer: FSP
• More Information: http://www.antec.com
• Average Price in the U.S.*: USD 40.00

* Researched at Newegg.com on the day we published this review.

Conclusions

We were extremely impressed by the Antec VP450 power supply, which proved to be an above average budget power supply.

Power supplies without a PFC circuit usually provide, at least at some point, efficiency below 80 percent. However, this simply didn’t happen with the VP450, which presented efficiency between 80.3% and 85.5 percent. This unit, though, can’t qualify for the 80 Plus certification, as a PFC circuit is required to obtain it.

In addition, most budget power supplies have a fake label that says the unit has two +12 V virtual rails, while in reality the power supply doesn’t have an over current protection circuit, which is necessary for the power supply to have more than one +12 V rail. This doesn’t happen with the VP450, which really has two +12 V over current protection channels.

With so many bad power supplies sold for USD 40 or less (several of which can really damage your PC due to voltages outside the proper range), the Antec VP450 is a terrific find. If you are building an entry-level PC that doesn’t require a lot of power, you and your wallet will be very happy with the VP450.