Antec EarthWatts EA 380D Green 380W

Antec has been around for nearly a quarter of a century, making them one of the grandfathers of the modern computer industry. Well known for their cases and power supplies, we've looked at the EarthWatts line a couple of times in years past. Antec has updated the EarthWatts line with their new Green models, sporting a dark green exterior and more environmentally friendly packaging—including the removal of the power cord, since most users already have a surplus.

Unlike so many other power supplies, it's nice to see a sensibly rated unit for a change. 380W is still plenty even for a midrange system, and with optimal efficiency generally coming at 50% load this is a power supply that should run closer to its "sweet spot" when idle as well as under load. There's still enough power on top to run a Core i7 or Phenom X6 processor and a discrete GPU, but you'll want to stick with graphics cards that only require a single PCIe power connection to err on the side of caution.

The EA-380D like any decent modern power supply also carries an 80 Plus certification, this time for the Bronze level. That means the PSU should run at 82% efficiency with a load of 20% (76W), reaching 85% efficiency or more at a load of 50% (180W), and still maintain 82% efficiency at the maximum 380W rated load. This is nothing ground-breaking in late 2010, but it does fit perfectly with moderate systems that can idle at under 100W. Just how green is the new EarthWatts? Let's find out as we explore some of the other features.

Package Contents

The EA-380D (and the rest of the EarthWatts Green line) ships without a power cord. The supposed reasoning is that most households already have extra power cords, as they accumulate from older PCs and upgrades, but if you're new to the computing game you may have to order one (or ask a friend). While that may benefit the environment, it's also worth noting that Antec saves a bit on costs; the customer will have to decide whether the included matierials are sufficient.

Antec neglected to mention the absense of polystyrene in their packaging; the PSU is protected by two pieces of recycled cardboard. Also included are mounting screws and a product overview sheet. Besides the “green philosophy”, the removal of the power cord (~1$) is a useful way of reducing BOM costs, whereas the manual and screws are rather inexpensive by comparison. We would say that screws could be left out as well, since they could be reused from older PCs, but they cost (and weigh) less, so the there was apparently less incentive to remove them.

Going with the green image, a dark green coating was selected for this series; it's an unusual alternative to the grey predecessors and other (mainly black) retail PSUs. It won't matter one way or the other for windowless cases, but some customers might enjoy the change in style. The varnish resists scratches very well and fingerprints are not visible. With an 80mm fan at the rear of the chassis, there are no bulging fan grilles on the top or bottom. The ventilation holes are square-shaped and give the PSU an angular and rustic appearance. Otherwise the styling is straightforward and unobtrusive. With a depth of just 14cm, it is the smallest possible ATX-size PSU.

The +12V rails are rated at 15A and 17A respectively and deliver a combined 336W. +5V and +3.3V are specified with 20A and 115W combined. The peak power on the stronger rails is 450W.

Cables and Connectors

A small rubber ring protects the outgoing cables from damage caused by rubbing against the casing. Except for the 24pin-cable, all of he cables are unsleeved, which again keeps costs down. A few cable ties help keep the cables somewhat organized. If you're used to higher end PSUs, the cabling on the EarthWatts Green looks like a throwback to older/cheaper designs, but the internals are still modern.

The number of connectors is adequate for the PSU capacity. Five SATA and four PATA plugs are enough for the HDDs and other peripheral hardware of most systems. The 24-pin, 4+4-pin ATX12V and 6-pin PCIe-cords have a length of 50 cm. This is average and we have seen longer cables, but this PSU will mainly be used in Mid- or Mini-Towers.

Internals

After opening the PSU, a well-structured design can be seen with two rather slim heat sinks, which are positioned according to the airflow. Similar to the first EarthWatts models (designed by Seasonic), the heat sinks don’t form a tunnel topology, which means that the airflow isn’t as linear as we have seen elsewhere--i.e. an Arctic Cooling PSU with their thoughtfully positioned air foil. But there is less energy dissipating into heat because of the lower nominal power and higher efficiency and there are large spaces inside where the air is able to circulate. The position of the rectifier bridge with its heatsink and the EMI-filter slightly hinder the airflow.

The IEC-plug is followed by the mains switch, which engages the phase conductor when thrown. Two Y-caps are connected with a protective ground wire, which is securely fixed on the case. Additional glue would be useful to improve mechanical stability. Well-twisted phase and neutral wires are coiled around an additional ferrite core and securely soldered. If wires are not twisted well, the connection could easily break. [Note: The quality in Chinese factories is still fluctuating.]

Two common mode chokes, four Y-caps, and two X-caps follow, with another X-type cap located behind the rectifier bridge; however, a varistor is missing. From this perspective we can see how precisely the chokes are fixed. In the power factor pre-regulator, we find a Samxon capacitor with the model number MXL. The Champion-IC 6800AG regulates the PFC and the main circuit of the PSU. This IC features OCP (Over Current Protection) and short circuit protection and has become popular because of its low-loss controlling.

Since the glue can’t always be positioned accurately, the 12V-choke is stabilised with a socket, which is useful at certain sizes. The costs are higher and the processing is more complicated. This kind of fastening is more likely to be found in high-end models. Sometimes this method is impossible, since the space is limited. The last model with this feature was the Enermax Revolution85+ 850W, where the size of the PFC-choke was the problem. In the OEM sector it is common to fix the components above necessity.

The +12V rail is filtered by Nippon Chemi-Con (KZE) and Ltec (LZG) capacitors, while on the smaller rails a potpourri of Nippon Chemi-Cons, Ltecs, and a single Taicon are used. A metering diode on a heat sink measures the temperature.

The noted build quality continues with a high soldering quality. Most conducting paths are cleanly soldered, but the output cables of the secondary circuit had to be cut so the wires don’t protrude too much under the PCB. Usually the manufacturer should be able to estimate the lengths of the wire when using THT-components. Connections could break if protruding wires are cut off. On the solder points of phase and neutral wires, solder residue can be found because of a very high soldering temperature, but there are no damages visible.

Voltage Regulation

The voltage drops are minor at all loads. +12V slightly rises at 20% load to work against the voltage drop at higher currents. With 4.90V the +5V rails reaches its highest drop at 12.56A and ranges just above the nominal value at 10%. At similar loads +3.3V rail reaches 3.28V. Both +12V rails are within specification and show a nearly identical trend. 11.94V is the lowest value at 110% load (13.49A on the bigger rail). Even if you overclock, you won’t fall below tolerance on a single wire of the CPU connector.

Efficiency & PFC

The sample reaches just 78% efficiency at 10% load, but at all other loads it's above 80%. The peak efficiency on 230VAC is 87.58%. At higher loads it slightly decreases and 83-84% is reached at full load. These are common results. The power factor reaches between 0.858 and 0.964. If we switch to 115VAC, the power factor always stays above 0.900 with a maximum of 0.984.

Cooling & Noise Level

Objectively the noise level is above the level of the quietest PSUs, which often start below 20 dBA. But the increase is moderate until load reaches 80%. After that, the RPMs increase quickly, which results in nearly 35dBA at overload. But there is sufficient cooling because the exhaust air always stays cool and the result is a higher lifespan of the PSU.

Like the first generation of the EarthWatts PSUs, Antec is using an ADDA-fan (AD0812H5-A70GL), which has a ball bearing and a power consumption of 0.25A. The fan draws the warm air out of the rear of the PSU. With a fan vertically mounted to the PCB, heat-sensitive components have to be placed in the airflow. The air flows relatively unobstructed through the case, while top blowing fans guide the air first to the PCB and then to the outside. So basically it doesn’t matter which concept is chosen because both ideas have advantages and disadvantages. The fan itself and its control mode is more important.

Ripple & Noise

There are no significant overshoots visible in the graphs. The fundamental oscillation is minor as well, which means very low ripple & noise. In addition the voltage always regulates itself around the same value. +5V reaches 10-25 mV at 100% to 110% load in our tests. The result at +3.3V is just marginally higher. 70 mV on the stressed +12V rail is just above 50% of the allowed tolerance. Here we have shown the worst case and the measurements are representative, so the results are fine. During all of the tests the oscilloscope showed no noticeable transients of the voltage.

Conclusion: No Need for 1.21 KW of Power!

There's certainly an emphasis on reducing power use and costs these days, with some governments pushing legislation to penalize companies that don't at least give some attention to the environment. Antec has worked hard to promote the image of a "green" and environmentally friendly PSU with their updated EarthWatts line—even going so far as to put green in the name and give it a dark green paint job!—but at the end of the day it's the product quality that determines whether something is worth buying. How well does the EarthWatts Green actually do when it comes down to real world metrics with no marketing fluff? Thankfully, Antec acquits itself well and produces an inexpensive yet well-built and efficient PSU.

While the marketing department might tout such benefits as the lack of a power cord and 80 Plus certification, let's be honest: removing the power cord probably did more for the company's bottom line than the environment, and 80 Plus certifications are everywhere. Still, there's nothing wrong with avoiding yet another power cord in the storage bin, and 80 Plus Bronze certification in a 380W PSU is a rarity. The fact of the matter is that many PCs don't have high-end CPUs and GPUs that need boatloads of power, but if you shop around for quality 300W PSUs for such systems, your choices become very limited.

We did a quick search on Newegg for 350W-400W PSUs like the EarthWatts Green to see what we could find. At present, there are eleven such PSUs: three "Standard" 80 Plus, seven Bronze PSUs like the Antec, and one Gold. While you might be tempted to go for the gold, so to speak, the Seasonic X Series SS-400FL comes in with a brutally high cost of $139. For that much money, you can buy three Antec EarthWatts Green PSUs (and still have $5 left for lunch after shipping)! The three 80 Plus Bronze PSUs in this range priced lower than the EarthWatts come from Raidmax, Xigmatek, and Sigma; two of those companies (Raidmax and Sigma) don't exactly have the best reputation in the quality department, and we're more than willing to pay a bit extra for the Antec EarthWatts.

What you get for your $45 is a good PSU for entry-level and midrange systems that won't be heavily overclocked or run multiple GPUs—you can still do a fair amount of overclocking if you're so inclined, though that flies in the face of being green I dare say. The cable lengths are suitable for mid-tower and smaller cases, there are sufficient connectors for the target market, and overall build quality, voltage regulation, and efficiency are very good.

There's been a distinct lack of focus on the "normal" PSU market over the past few years, with more and more companies going for the high margin 700W and higher market. Antec's back-to-basics approach with the EarthWatts line is appreciated, and the price and availability is a great value for what you get. For those that want something reasonable instead of chasing ORB and overclocking records, the Antec EarthWatts EA-380D is a great little PSU that's worth your dollar, and we're presenting it with our Bronze Editor's Choice award. You can buy power supplies that are more efficient, higher capacity, quieter, or cheaper, but there are tradeoffs with any one of those. The EA-380D strikes a nice balance and won't break the bank while meeting your power needs.