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- Date:
- Thursday , July 02, 2009
- Author:
- Paul Johnson
- Editor:
- Kyle Bennett
- Google +1
Enermax Liberty Eco 620W Power Supply
Enermax has been one of our favorite computer Power Supply Unit builders for many years. It has constantly driven quality products into the market place. Today we kick the tires on the Liberty to celebrate the upcoming 4th of July.
Build Quality
As we already know from the product images and packaging the Liberty Eco 620W features a single 135mm fan design that has come to be the preferred standard for quiet cooling environments due to the ability to move a larger volume of air at slower speeds than a smaller diameter fan. While great for quiet computing environments the key criteria in our evaluation is whether or not the cooling solution is sufficient, not necessary it’s sound level or form factor. Our previous experience Enermax power supplies have yielded relatively quiet units so the Revolution has some potential to be quiet if Enermax can execute as well this time as they did last few times especially since this unit is advertised as having a very good fan controller.
External Build Quality
The external build quality of the Liberty Eco is identical to the MODU82+ with the slight exception being the color of the finish. The unit comes trimmed out in a flat textured black as opposed to the MODU82+'s slightly reflective brushed grey finish, yet both feature a clear fan and gold fan grill. Following the lead of the MODU82+, the Liberty Eco 620W has APFC and it lacks the LED from other Enermax units we have reviewed that was used for the PowerGuard feature. The front of the unit is identical to the MODU82+'s with its modular connectors pinned out in one single vertical row. We also see, as was the case with the MODU82+, that the PCIe cable connectors really do use proprietary modular connectors with twelve pins on the housing end of the cable.
The Liberty Eco 620W comes in at a trim 5 1/2 inches while the cables provide a serviceable length of ~18 inches to the first or only connector, which is certainly long enough for most applications. The sheathing on the cables, both fixed and modular, is like we have seen in previous Enermax units in that it is multicolored without being gaudy but it is short of being complete on both ends of the modular cables.
Internal Build Quality
Once the screws securing the fan housing are removed we are once more left looking at a very standard power supply design that seems almost identical to the MODU82+. The unit once again has a single transformer for the 12v rails that is provided by Rong Chyuan but this time it bears a different part number than what was found in the MODU82+. Additionally, the heatsinks that Enermax has employed here are the same as those in the MODU82+, as is the fan. The fan selected by Enermax to cool this unit is once more a bit unusual as it is the same Enermax registered (at the UL at least) bi-voltage fan rated at 0.3a at 12v as we saw in the MODU82+. While it goes without saying that changing out a fan in a power supply will void a users warranty, in the case of the Liberty Eco 620W instead of just voiding your warranty there is a very real chance that swapping fans will, at the very least, result in a fan that does not work properly. As such, we would strongly recommend users NOT swap fans in this power supply for any reason.
Over on the primary side of the unit we see that it looks generally clean like the MODU82+, however the toroid coil once more looks odd. As we see in side view image it is set very high off the PCB while the only thing supporting it is the zip-tie on the heatsink. Enermax claims that this method of securing the coil is actually more secure than affixing it to the PCB but having the legs of the coil that exposed off of the PCB certainly looks oddly done and it does not appear that the primary could not have been reworked in order to place the coil on the PCB in a more traditional manner (and then secured with a zip-tie). We have discussed this with Enermax more than once and it is sure of its design. We also see on the primary side that the unit features two capacitors provided by Matsushita and rated at 220uF 400v 85c even though the unit features APFC as was the case with the MODU82+. Lastly, the small golden colored heatsink is once more attached to the bridge rectifier. All in all, this primary side design looks identical to that of the MODU82+ we have been comparing it to all along which is interesting.
As we move over to the secondary we notice that similarities with the MODU82+ continue. The input filtering is mostly housed on a small PCB attached to the AC receptacle while there is no other add-in PCB on the secondary side. This is due to the fan controller and output protection circuitry all being housed on the unit’s main PCB. The capacitors selected for this unit are once more CEC International Holdings Limited capacitors as we have seen on some previous Enermax offerings (the MODU82+ was stocked with Nippon Chemi-con capacitors so this may be somewhat of a step down in quality). The wiring that surrounds these capacitors is well tended and neat with the majority of the wires being very short as they are run to the PCB that houses the modular interface. The modular interface appears to be well constructed and clean for the most part. However, when we look at the middle of the PCB we see what is one of the largest runs of solder we have seen in a power supply not sold by Topower/Tagan. Enermax claims that the increased current capacity necessitates thicker hand soldered traces here which is partially true. Larger current capacities do require thicker traces, but many other OEM's/brands have accomplished this same current capacity (or greater) with robotic and/or clean soldering, so the untidy hand soldering is certainly not necessary here.
Build Quality Summary
Overall the Liberty Eco 620W build quality is very much like that of the MODU82+ build quality but it does trail it slightly. The exterior of the unit is well done once more as are most aspects of the interior. The primary is stocked with Matsushita capacitors but the levitating PFC coil still looks a bit out of place no matter how good of a job that zip-tie is doing. On the secondary, Enermax has returned to the CEC International Holdings Limited capacitors that we have seen in previous models which may seem to many people to be a step down from the Nippon Chemi-con of the MODU82+. However, in general these capacitors have not be overly problematic in Enermax units but we would be remiss if we did not at least note that this unit, while very much like the MODU82+, does differ in this regard from the MODU82+. Overall, for a unit being pitched as a value unit this unit looks very much like what Enermax was pitching as an enthusiast unit last year, which isn't really a bad thing. Let's hope this unit can perform like that previous unit as well as we move on to the load testing.