Antec TruePower Quattro 850 W Power Supply Review

[nextpage title=”Introduction”]

TruePower Quattro 850 W is a power supply from Antec featuring modular cabling system, four auxiliary PCI Express power cables for video cards, active PFC, efficiency above 80% and the very traditional ATX looks, with a small 80 mm fan on the rear side. The manufacturer promises that this unit can deliver its labeled power at 50° C. Sounds promising, but can this unit really deliver 850 W? Let’s see.

Figure 1: Antec TruePower Quattro 850 W power supply.

Figure 2: Antec TruePower Quattro 850 W power supply.

As we mentioned this power supply uses a regular 80 mm fan on its rear instead of a 120 mm or bigger fan on its bottom.

We like modular cabling systems as they allow you to only have the cables you are really going to use, improving the airflow inside your PC since you will have fewer cables blocking the airflow. Usually on power supplies that use modular cabling systems the motherboard cables don’t use them, being permanently attached to the power supply. This isn’t an issue, as you will always use the motherboard cables. On this power supply, however, two of the four auxiliary power cables for video cards don’t use the modular cabling system, being permanently attached to the unit (these cables use 6/8-pin connectors). In theory this shouldn’t be an issue, as this power supply is targeted to users with at least two video cards installed under SLI or CrossFire. If you have just one video card installed, then you will have one unused video card power cable hanging from the power supply. Also you will always have one of the motherboard cables hanging loose, as this power supply has separated EPS12V and ATX12V cables and you can only have one of the two attached to your motherboard.

On the power supply modular cabling system the manufacturer identified which +12 V rail each plug is connected to. This is a terrific idea.

Figure 3: Identification of which +12 V rail each plug is connected to.

In Figure 4, you can see the cables from the modular cabling system that include two 6-pin auxiliary cables for video cards, three cables with three standard peripheral power plugs each (two of them with a floppy disk drive power connector attached), two cables with three SATA power plugs and one cable with two SATA power plugs.

The number of connectors provided by this power supply is perfect for even the most high-end user.

Figure 4: Peripheral cables.

On this power supply all wires are 18 AWG, except the wires on the main motherboard cable, which are 16 AWG, which is adequate for a power supply on this power range.

Even though Antec paid to have their own UL number, this power supply is actually manufactured by Enhance Electronics.

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

[nextpage title=”A Look Inside The Quattro 850 W”]

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, and then in the following pages we will discuss in detail the quality and ratings of the components used.

Figure 5: Overall look.

Figure 6: Overall look.

Figure 7: Overall look.

[nextpage title=”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 transient filtering stage from this power supply is outstanding, with four extra Y capacitors, two extra X capacitors and a ferrite bead attached to the main AC cable. This power supply also provides an X capacitor after the rectifying bridge.

Figure 8: Transient filtering stage (part 1).

Figure 9: Transient filtering stage (part 2).

In the next page we will have a more detailed discussion about the components used in the TruePower Quattro 850 W.

[nextpage title=”Primary Analysis”]

On this page we will take an in-depth look at the primary stage of Antec TruePower Quattro 850 W. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.

This power supply uses two GBU1005 rectifying bridges connected in parallel in its primary, each one capable of delivering up to 10 A at 100° C, so the total capacity is of 20 A at 100° C. These two bridges are attached to a heatsink. This section is clearly overspec’ed: at 115 V this unit would be able to pull up to 2,300 W from the power grid; assuming 80% efficiency, the bridges would allow this unit to deliver up to 1,840 W without burning thse components. Of course we are onl
y talking about this component and the real limit will depend on all other components from the power supply.

Figure 10: Rectifying bridges.

The active PFC circuit uses two STW25NM50N power MOSFET transistors, each one capable of handling up to 14 A in continuous mode at 100° C (or 22 A at 25° C; see the difference temperature makes) or 88 A in pulse mode at 25° C. These transistors are located on the same heatsink as the switching transistors.

On the switching section this power supply uses a rather different design. It uses a modified single-transistor forward configuration using a second transistor in the place of the required diode. The main transistor is a STW15NK90Z, capable of delivering up to 9.5 A continuously at 100° C (or 15 A at 25° C; once again see the difference temperature makes) or 60 A in pulse mode at 25° C. The second transistor that was installed replacing the diode is a FQPF8N80C, which can deliver up to 5.1 A at 100° C (8 A at 25° C) continuously or up 32 A in pulse mode.

Figure 11: Switching transistor, support transistor, PFC diode and active PFC transistors.

The primary section is controlled two separated integrated circuits, one for the active PFC circuit (ICE1PCS02) and one for driving the switching transistor (i.e., PWM, NCP1280), instead of using just one combo controller as it happens with almost all modern power supplies. These integrated circuits are located on separated small printed circuit boards that are attached to the main printed circuit board.

Figure 12: Active PFC controller.

Figure 13: PWM controller.

[nextpage title=”Secondary Analysis”]

This power supply uses a synchronous topology on the secondary. This is the second power supply we’ve seen using such design (the other one was OCZ ProXStream 1000 W). On this topology the diodes are replaced with MOSFET transistors. In theory this configuration provides a higher efficiency, as MOSFET transistors have a lower voltage drop compared to Schottky rectifiers (0.1 V or less vs. 0.5 V). This leads to less power wasted and thus higher efficiency.

For rectifying the +12 V output four IRL2203N power MOSFET transistors are used, each one capable of handling up to 82 A at 100° C in continuous mode, or up to 400 A in pulse mode (at 25° C). The maximum theoretical current the +12 V 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 (which in this case was replaced by two 82 A transistors in parallel). Just as an exercise, we can assume a typical duty cycle of 30%. This would give us a maximum theoretical current of 234 A or 2,811 W for the +12 V output – which is clearly overspec’ed. The maximum current this line can really deliver will depend on other components, in particular the coil used.

For rectifying the +5 V output two IRL3705Z power MOSFET transistors are used, each one capable of handling up to 61 A at 100° C in continuous mode, or up to 340 A in pulse mode (at 25° C). This would give us as maximum theoretical current of 87 A or 436 W for the +5 V output.

And for rectifying the +3.3 V output other two IRL3705Z power MOSFET transistors are used, giving a maximum theoretical current of 87 A or 287 W for this line.

Of course this is just an exercise and the maximum current the power supply can really deliver depends on the other components. But we could see that the rectification circuit is clearly overspec’ed.

The +5VSB output uses a regular Schottky diode pack, SR1060, capable of delivering up to 10 A at 25° C.

Figure 14: Two +12 V transistors, +5 V transistor, +3.3 V transistor and +5VSB rectifier. The other transistors are on the other side of the heatsink.

This power supply uses a PS223 monitoring integrated circuit, which is in charge of the power supply protections, like OCP (over current protection). OCP was really activated, as we will talk about later. This IC also provides over voltage protection (OVP), under voltage protection (UVP) and over temperature protection (OTP), but not over power protection (OPP).

Figure 15: PS223 monitoring integrated circuit.

This power supply has two thermal sensors: one for controlling the speed of the fan and one for shutting down the power supply in case of an overheating situation (i.e., OTP, over temperature protection). It is interesting to note that Antec doesn’t list OTP as a feature for this power supply, but the monitoring IC supports this feature and it is connected to a thermal sensor.

Figure 16: Thermal sensors.

The active PFC electrolytic capacitor is Japanese from Chemi-Con (rated at 105° C) but the secondary capacitors are Taiwanese, from Teapo (rated at 105° C).

[nextpage title=”Power Distribution”]

In Figure 17, you can see the power supply label containing all the power specs.

Figure 17: Power supply label.

As you can see this power supply has four virtual +12 V rails. These rails are distributed like this:

• +12V1 (yellow with black stripe wire): EPS12V and ATX12V connectors.
• +12V2 (solid yellow wire): Peripheral and SATA power connectors.
• +12V3 (yellow with blue stripe wire): Main motherboard cable, one of the 6/8-pin video card auxiliary power connectors that is permanently attached to the power supply and one of the 6-pin video card auxiliary power connectors that is available on the modular cabling system.
• +12V4 (yellow with green stripe wire): one of the 6/8-pin video card auxiliary power connectors that is permanently attached to the power supply and one of the 6-pin video card auxiliary power connectors that is available on the modular cabling system.

We think this power distribution is ok, but we think that the main motherboard cable should be on +12V2 and not on +12V3.

Now let’s see if this power supply can really deliver 850 W of power.

[nextpage title=”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 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.

+12V2 is the second +12V input from our load tester and during our tests it was connected to the power supply EPS12V – i.e., to the +12V1 rail. The +12V1 input was connected to the +12V2, +12V3 and +12V4 rails.

Input	Test 1	Test 2	Test 3	Test 4	Test 5
+12V1	6 A (72 W)	13 A (156 W)	20 A (240 W)	25 A (300 W)	31 A (372 W)
+12V2	6 A (72 W)	12 A (144 W)	17 A (204 W)	25 A (300 W)	31 A (372 W)
+5V	2 A (10 W)	4 A (20 W)	6 A (30 W)	8 A (40 W)	10 A (50 W)
+3.3 V	2 A (6.6 W)	4 A (13.2 W)	6 A (19.8 W)	8 A (26.4 W)	10 A (33 W)
+5VSB	1 A (5 W)	1.5 A (7.5 W)	2 A (10 W)	2.5 A (12.5 W)	3 A (15 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	173.7 W	350.5 W	514. W	689. W	850.4 W
% Max Load	20.4%	41.2%	60.5%	81.1%	100.0%
Room Temp.	47.1° C	47.6° C	47.8° C	48.6° C	50.1° C
PSU Temp.	48.6° C	49.5° C	48.2° C	48.7° C	50.1° C
Load Test	Pass	Pass	Pass	Pass	Pass
Voltage Stability	Pass	Pass	Pass	Pass	Pass
Ripple and Noise	Pass	Pass	Pass	Pass	Fail
AC Power	201 W	397 W	588 W	809 W	1033 W
Efficiency	86.4%	88.3%	87.4%	85.2%	82.3%
Final Result	Pass	Pass	Pass	Pass	Fail

This power supply could deliver its rated power at 50° C – which would be perfect if noise level didn’t go out of spec at +5 V line after working for just one minute at this temperature.

Working at 45° C noise level at the +12V1 input from our load tester was at 49.4 mV, at the +12V2 input was at 36.8 mV, at the +5 V was at 23.2 mV and at the +3.3 V was at 28 mV. These are very good results. But after temperature increased to 50° C noise level started to increase after just one minute, jumping to 88 mV at the +12V1 input from our load tester (i.e., at the +12V2 rail from the power supply) and to 62.8 mV at the +5 V output, making the power supply to work out specs, as the maximum admissible noise level for this output is of 50 mV.

Not only that. Even at 45° C noise level at +5VSB was out of range, at 65.8 mV. This is the first time we’ve seen a power supply with such high noise level at this output.

Below you can compare what happened after working one minute at 50° C.

Figure 18: +12V1 input from our load tester at 850 W at 45° C.

Figure 19: +12V1 input from our load tester at 850 W after one minute at 50° C. See the big spikes.

Figure 20: +5 V line with power supply delivering 850 W at 45° C.

Figure 21: +5 V line with power supply delivering 850 W after one minute at 50° C. See the big spikes.

Figure 22: Noise level at +5VSB was above 50 mV.

Taking out this “detail” it isn’t a bad power supply. It reached efficiency between 82.3% and 88.3%, staying always above 85% if you pull up to 80% of the power supply nominal power (i.e., up to 680 W).

Voltage regulation was excellent and during all our tests all outputs were within 3% of their nominal voltages – ATX specification defines that all outputs must be within 5% of their nominal voltages (10% for -12 V) –, except -12 V (this output was within the 10% tolerance set by ATX specification).

Now let’s see if we could pull even more power from this unit and our tests of the power supply protections.

[nextpage title=”Overload Tests”]

Before performing our overload tests we always like to test first if the over current protection (OCP) circuit is really active and at wha
t level it is configured.

We configured +12V1 input from our load tester with a low current (1 A) and increased current on +12V2 input (which was connected to the power supply +12V1 rail through the EPS12V connector) until the power supply shut down. This happened when we tried to pull more than 32 A, so OCP was active and set at 32 A. A value that is too high in our opinion, as the power supply label says that each rail has a limit of 18 A. We prefer when the over current protection is configured to a value closer to what is printed on the product label.

Unfortunately this power supply does not feature over power protection (OPP).

Then we tried to pull even more power from TruePower Quattro 850 W. The problem, however, was the noise level. As you know we were already facing noise issues with the power supply delivering 850 W. We could pull even more power from this unit, but noise level was always outside the maximum admissible according to the ATX standard (maximum of 120 mV for +12 V outputs and 50 mV for +5 V and +3.3 V outputs). The main problem was with the +5 V and +5VSB outputs. While noise level at +12 V outputs was high, it was still below 120 mV. Noise at +5 V, however, was at least at 70 mV and at +5VSB was at 87 mV.

So we can’t consider that we could successfully pull more power from this unit, as we can only consider results where the power supply is still working within ATX specs.

Short circuit protection (SCP) worked fine for both +5 V and +12 V lines.

And we’d like to remind here that even though we didn’t test it, over temperature protection (OTP) is enabled and Antec doesn’t mention this important feature on their website.[nextpage title=”Main Specifications”]

Antec TruePower Quattro 850 W power supply specs include:

• EPS 2.91
• Nominal labeled power: 850 W at 50° C.
• Measured maximum power:850 W at 50° C.
• Labeled efficiency: Between 80% and 85%.
• Measured efficiency: Between 82.3% and 88.3% at 115 V.
• Active PFC: Yes.
• Motherboard Power Connectors: One24-pin connector, one ATX12V and one EPS12V connectors.
• Video Card Power Connectors: Four, two 6/8-pin connectors and two 6-pin connectors.
• Peripheral Power Connectors: Eight.
• Floppy Disk Drive Power Connectors: One.
• SATA Power Connectors: Six.
• Protections: over voltage (OVP, not tested), under voltage (UVP, not tested), over current (OCP, tested and working), over temperature (OTP, not listed by the manufacturer but present, not tested) and short-circuit (SCP, tested and working).
• Warranty: Five years.
• Real manufacturer: Enhance Electronics
• More Information: https://www.antec.com
• Average price in the US*: USD 200.

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

[nextpage title=”Conclusions”]

Antec TruePower Quattro 850 W is a though competition to Cooler Master Real Power Pro 850 W. They are both could really deliver 850 W at 50° C during our tests, both can be found at the same price range and both are manufactured by the same company (Enhance Electronics) – using completely different designs, though.

Both achieved a very good efficiency, with the reviewed model from Antec achieving above 85% when we pulled up to 80% of the power supply capacity. When we pulled the full 850 W efficiency was still above 82%.

The only problem with Antec TruePower Quattro 850 W was that voltages weren’t “clean” when delivering 850 W at 50° C: noise level was above the maximum admissible. That was the only problem we had with this unit. With temperature below that noise level was just fine.

Since we hadn’t this problem with Cooler Master Real Power Pro 850 W and also we could pull up to 1,000 W with this unit from Cooler Master at 50° C with noise level below the maximum admissible (what we couldn’t with TruePower Quattro 850 W), we are more inclined to recommend this model from Cooler Master over the reviewed Antec product.

On the other hand this model from Antec brings a modular cabling system, feature not present on this model from Cooler Master.

Both models have over temperature protection (OTP), a not so common feature, but they both don’t have over power protection (OPP), which is a shame for models on this power and price ranges.

If you aren’t going to pull nowhere near 850 W – which is the case for 99.99% of users buying this power supply – this is a good buy and the problem we had during our tests won’t affect you.

But carefully research before buying, as prices change a lot depending on the store. The right price for TruePower Quattro 850 W is below USD 200, but we’ve seen some stores selling it by USD 250.