In the automotive world, being green is all the rage. No manufacturer wants to be caught without at least one model aimed squarely at that demographic. And sure, the government gets involved by compelling the industry to move toward cars that consume less fuel and pump out fewer emissions into the atmosphere. The response isn't surprising: our more mainstream cars trade power for higher efficiency.
The same general principle can be applied to power supplies. Today's processors are far less power-hungry than their predecessors. Even gaming-oriented PCs built for performance seldom suck down more than 450 W. Better efficiency, on the other hand, is good for both the environment and your wallet.
So, we went into this round-up with the following two requirements for the participants: their submissions couldn't exceed 450 W and they needed to be efficient. In order to keep prices within reason, we settled on an 80 PLUS Gold rating as sufficient to meet our second demand.
Technical Specifications
| Products |
CoolerMaster V4505
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Corsair RM450
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Enermax Revolution X't 430W
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Seasonic S12G 450W
|
| Pricing |
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| Certification | 80 PLUS Gold | 80 PLUS Gold | 80 PLUS Gold | 80 PLUS Gold |
| Dimensions (WxDxH) | 150 x 140 x 86 mm | 150 x 160 x 86 mm | 150 x 160 x 86 mm | 150 x 140 x 86 mm |
| Weight | 1.6 kg | 2.76 kg | 1.8 kg | 2.16 kg |
| Operating Temperature | 0 to 40 C | 0 to 50 C | Up to 40 C | 0 to 40 C |
| Warranty | Five Years | Five Years | Five Years | Five Years |
| Specification | ATX12V v2 | ATX12V v2.4 | ATX12V v2.4 | ATX12V v2.4 |
| Specified Power Output | 450 W | 450 W | 430 W | 450 W |
| Maximum Peak Output | N/A | N/A | 475 W | N/A |
| AC Input | 100 - 240 V | 100 - 240 V | 100 - 240 V | 100 - 240 V |
| AC Voltage Selection | Auto Voltage | Auto Voltage | Auto Voltage | Auto Voltage |
| DC Output +3.3 V | 20 A | 24 A | 20 A | 20 A |
| DC Output +5 V | 20 A | 22 A | 20 A | 20 A |
| DC Output +12 V | 36 A | 37.5 A | 35 A | 37 A |
| DC Output -12 V | 0.3 A | 0.8 A | 0.8 A | 0.3 A |
| DC Power +12 V Combined | 432 W | 450 W | 420 W | 444 W |
| PFC | Active | Active | Active | Active |
| Specified Hold-Up | > 16 ms | 16 ms | 16 ms | > 16 ms |
| MTBF | 100,000 hours | 100,000 hours | 100,000 hours | 100,000 hours |
| Fan | 120 mm | 135 mm | 139 mm | 120 mm |
| Fan Speed | N/A | Up to 924 RPM | 600 to 1300 RPM | Up to ~2100 RPM |
| 20+4 pin Motherboard | 1x (60 cm) | 1x (60 cm) | 1x (55 cm) | 1x (55 cm) |
| CPU | 1x (60 cm) | 1x (65 cm) | 1x (60 cm) | 1x (60 cm) |
| PCI Express 6-pin/6+2-pin (Graphics) | 0/2x (55 - 65 cm) | 0/2x (60 - 75 cm) | 0/2x (45 cm) | 0/2x (60 - 70 cm) |
| Molex 4-pin (Peripherals) | 3x (40 - 70 cm) | 4x (45 - 75 cm) | 4x (45 - 90 cm) | 3x (50 - 70 cm) |
| SATA Power | 6x (40 - 70 cm) | 6x (50 - 70 cm) | 8x (45 - 90 cm) | 8x (50 - 80 cm) |
| 4-pin Floppy | 1x (85 cm) | 1x (90 cm) | 1x (105 cm) | 1x (80 cm) |
| Accessories | Screws | Screws, Cable ties, Fan cables | Screws, Velcro Strips, Cord Guard | Screws, Velcro Strips, Cable Ties |
| Cable Management | Yes | Yes | Yes | No |
| Other Details | N/A | Fanless Mode | Fans run 30 to 60 seconds after powered down. | N/A |
Four vendors stepped up to our challenge. Seasonic offered its S12G at 450 W, which is currently selling for $75. Enermax sent in its Revolution X't, rated for 430 W and available at $90. Spend an additional $10 and you can get Corsair's RM450, which, as its name suggests, is rated for up to 450 W. Cooler Master submitted its V450S. And although that unit appeared promising, it isn't available in the U.S. That makes Seasonic's power supply the least-expensive option in our field, which isn't something you might have expected.
We haven’t heard much from Enermax lately. The company once had a pristine reputation though, so we wanted to check up on its status. The Revolution X't family is Enermax's second-best. Only the Platimax PSUs are a step up. Just one offering fit into our round-up: the 430 W Revolution X't, model number ERX430AWT.
This is a solid-looking power supply that makes a good impression. A rough, powder-coated surface, the piano-finish cooler, and semi-modular cabling all contribute to the sharp aesthetic. Cables are flattened, and their lengths can be considered generous. Further, the number of cables satisfies most requirements in this price class. There are two auxiliary 6+2-pin connectors for PCI Express-attached cards, an impressive eight SATA leads, and a quartet of four-pin Molex connectors.
The sole +12 V rail outputs up to 420 W, which is almost 98 percent of the rated power output. It’s also supposed to be able to deal with up to 35 A. Enermax equips the Revolution X't with five-year warranty coverage, too.
| AC Input | 100-240 V, 47-63 Hz | |||||||
|---|---|---|---|---|---|---|---|---|
| DC Output | +3.3 V | +5 V | +12 V (#1) | +12 V (#2) | +12 V (#3) | +12 V (#4) | -12 V | +5 Vsb |
| 20 A | 20 A | 35 A | N/A | N/A | N/A | 0.8 A | 3.0 A | |
| Individual Output | 32 A | 9 W | 1 W | |||||
| Rail Utilization | Sys | Sys | CPU & VGA | |||||
| Combined Output | 100 W | 420 W | ||||||
| Total Continuous Output | 430 W | |||||||
| Peak Output | 475 W | |||||||
As usual, our first step is putting together a report of power efficiency according to the 80 PLUS specification. All PSUs in this round-up sport the Gold certification and, consequently, need to have an efficiency of at least 87 percent at 10-percent load and full output. The efficiency has to be an even higher 90 percent at a load of 50 percent.
The Revolution X’t 430 W hits those numbers almost exactly. That's not a bad thing, since the performance is good enough to qualify, but you certainly can't expect any additional headroom for higher efficiency than 80 PLUS Gold. Still, the Enermax PSU manages to do well at low loads. A reading of 83.5 percent at 50 W is certainly reasonable. This power supply gets its job done without any fuss in the other test categories as well.
Finally, we’re taking a look at ripple measurements. The curve isn’t smooth on all rails, but it’s acceptable at 3.3 and 12 V. Only the 5 V rail ends up north of the 50 mV peak-to-peak border, registering 52.2 mV. Still, this is within our measurement tolerance.
The Revolution X’t 430 W's fan is always on. Corsair's RM450 is the only power supply in our round-up with dynamic fan control. Sure, the operating noise level is a very low 32.3 dB(A) at 40 W, but it's still audible as a soft purring noise in quiet environments. This noise level also makes Enermax's submission one of the louder contenders in this comparison. At medium load, which we simulate with 200 W, noise jumps up a bit to 33.1 dB(A).
A Look at the PCB
Enermax's Revolution X't 430 W is built by CWT. As is the de facto standard in this efficiency class, it uses a DC-to-DC topology. At first glance, the PSU’s interior appears messy. But that doesn't mean the quality isn't there. The soldering work is certainly up to spec, though we do think there's room for improvement.
The input filter design is executed well. Two X and four Y capacitors in combination with two inductors and a diode provide all that’s needed. The primary capacitor is made by Panasonic and can most certainly be counted in the highest-quality category. Enermax does try to save some money with the secondary capacitors, though. The CapXon logo tells us they're of decent Chinese quality, but that’s about it.
The power supplies in Cooler Master’s VS line are semi-modular. We imagine the company has to leave at least a benchmarkable delta between these units and its top-of-the-line V offerings. Still, we're presented with technical specifications that definitely don't reflect a budget-oriented model. In line with the rest of our field, Cooler Master's V450S is 80 PLUS Gold-certified. It also holds its own in our evaluation of power quality compared to the V-series.
Build-wise, the V450S feels solid. Its chassis is silver/gray and black, and very compact. As we've come to expect from Cooler Master, there's a single +12 V rail (though that's also par for this price and power category, too). According to the company, the V450S' +12 V rail is supposed to be good for up to 36 A, delivering up to 432 W.
Again, the VS line’s cables are semi-modular, which is to say that the motherboard, CPU, and auxiliary graphics card leads are fixed. They’re also round and sleeved. The other cables are modular and flat.
Cooler Master finishes last in our round-up when it comes to the number of connectors to which you have access. There are two PCIe, six SATA, and three Molex plugs. Cable length isn't a strong suit either. The fixed cables are relatively long, but the modular ones are simply shorter than competing units in today's story.
| AC Input | 100-240 V, 50-60 Hz | |||||||
|---|---|---|---|---|---|---|---|---|
| DC Output | +3.3 V | +5 V | +12 V (#1) | +12 V (#2) | +12 V (#3) | +12 V (#4) | -12 V | +5 Vsb |
| 20 A | 20 A | 36 A | N/A | N/A | N/A | 0.3 A | 2.5 A | |
| Individual Output | 3.6 W | 12.5 W | ||||||
| Rail Utilization | Sys | Sys | CPU & VGA | |||||
| Combined Output | 100 W | 432 W | ||||||
| Total Continuous Output | 450 W | |||||||
| Peak Output | n/a | |||||||
A look at the V450S' efficiency puts those shorter cables out of mind for a minute. No other power supply in this round-up comes close to its numbers, especially at low loads.
At 100- and 50-percent load, the V450S lands about one-half percent above what's necessary for 80 PLUS Gold certification. At 20 percent, it hits 89.7 percent (instead of the 87 percent required), which is about 2.5 percent better than the assembled competition. Moreover, its lead increases with lower loads. Barely any PSU out there can manage an efficiency of more than 80 percent at a 25 W load.
This takes us to the ripple and noise measurements. Everything looks good there well. We measure very little ripple on all rails, and a smooth curve tells a story of high-quality components.
The V450S' fan runs continuously, but it doesn’t generate as much noise as the Revolution X't's cooler. An acoustic output of 31.1 dB(A) measured at 50 W is very quiet. It doesn’t get much louder at medium loads, either. Cooler Master's V450S produces 31.6 dB(A) at 200 W.
A Look at the PCB
Cooler Master makes decisions similar to what we saw from Enermax. The OEM manufacturer Enhance, which is Cooler Master’s current favorite, built a modern design with an LLC (two inductor, one capacitor) topology and DC-to-DC converters for the smaller voltages. The VS family features a mix of Japanese and Chinese components as well. To that point, the large primary capacitor is made by Panasonic, while the secondary ones are built by Suncon.
There’s also a complete input filter design, and everything appears to be soldered well. Finally, there’s an eye-catching heat sink on the primary side of the PSU that’s rather large for a Gold-certified unit.
Although this power supply is available in Europe where our testing was conducted, Cooler Master doesn't sell it in the U.S. Regardless of how much we like it, only our readers overseas have access to the V450S.
Corsair’s description of its RM power supply family is very matter-of-fact. Gold-certified and fully modular are the two phrases used for marketing, and there's not much else to add except maybe that these PSUs are also optimized for quiet operation. After all, Corsair does enable hybrid fan control, meaning the fan stops when temperatures are low enough to support passive cooling. The outcome, of course, is silent operation in those cases (at least, that's how it's supposed to work in theory).
In any case, Corsair's build quality is good and the materials used are excellent. The RM450's matte black finish and rounded edges look nice, though the chassis isn't as compact as Cooler Master's and Seasonic's competing products. All of the bundled cables are modular and flat. As far as cable length and available leads go, Corsair lands in the middle of the pack. Its single +12 V rail is good for up to 37.5 A, according to the company's specifications. As we’ve seen before, the PSU comes with a five-year warranty.
| AC Input | 100-240 V, 47-63 Hz | |||||||
|---|---|---|---|---|---|---|---|---|
| DC Output | +3.3 V | +5 V | +12 V (#1) | +12 V (#2) | +12 V (#3) | +12 V (#4) | -12 V | +5 Vsb |
| 24 A | 22 A | 37.5 A | N/A | N/A | N/A | 0.8 A | 3.0 A | |
| Individual Output | 9 W | 1 W | ||||||
| Rail Utilization | Sys | Sys | CPU & VGA | |||||
| Combined Output | 110 W | 450 W | ||||||
| Total Continuous Output | 450 W | |||||||
| Peak Output | n/a | |||||||
A fully modular configuration has the advantage of more flexibility, especially when you need more specialized cables. The flip side of the coin, however, is an efficiency loss. Additional boards, conducting paths, and connectors all have a cumulatively negative impact on this important criteria.
As we might have expected, then, the measurements required for 80 PLUS Gold certification are a close call for the RM450. It manages to hit the three necessary benchmarks with no room to spare whatsoever. Lower loads look worse though, and those are what a normal PC will deal with most of the time. At 50 W, Corsair achieves an efficiency level of 80 percent. This drops all the way to 72 percent at 25 W.
Hold-up time is one of the RM450’s strengths, registering 24 ms. The ripple and noise measurements also speak to this power supply's high quality; they're similar to what we saw from Cooler Master's V450S. We also saw very low power consumption (.04 W) at standby without any load, which is great.
Thus far, Corsair's RM450 looks great. And, due to its dynamic fan control, it should also sail through our acoustic measurements. Then again, we’ve seen power supplies marketed as semi-passive that ended up sounding like hair dryers when their fans spun up.
Fortunately, Corsair's RM450 doesn't disappoint. Under a 200 W load, the fan didn't spin, and after 30 minutes of heat build-up, we were still waiting for it to make noise. We finally triggered the fan at 360 W, and even then it only generated a barely-noticeable 30.4 dB(A).
A Look at the PCB
Corsair has been working with CWT for years, and the RM family is a product of that collaboration. The chassis' build quality is high, similar to everything we find inside.
The input filter is separated into two parts consisting of two X and four Y capacitors, which work in conjunction with a MOV and two choke coils. The primary capacitor is made by Panasonic yet again. We find secondary ones from Nippon Chemi-Con and CapXon, the latter of which seems to be a popular Chinese supplier these days.
Corsair also uses a DC-to-DC converter topology, but skips the LLC and uses a somewhat dated IC instead. Nevertheless, this configuration is good enough to earn that Gold certification. Solder quality is consistent with what you should expect in this price category.
In past round-ups, Seasonic fared well with its X family of power supplies. They're notably fully modular and equipped with dynamic fan control. Additionally, the company is known for its fantastic build and component quality.
But for this story, Seasonic sent us the 450 W version of its S12G. For a price right around $75, you get a compact, 80 PLUS Gold-certified PSU with completely fixed cabling. That makes the S12G the only power supply in our round-up without cable management. In return, a combination of sleeved, round cables and flat cables turn out to be the long side, giving you plenty of room for routing. Moreover, you get two auxiliary PCIe connectors and eight for SATA-based drives.
Surprisingly, Seasonic's build quality doesn't quite match up to the competition. Similarities we do find are a single +12 V rail rated for up to 37 A and five-year warranty coverage.
| AC Input | 100-240 V, 50-60 Hz | |||||||
|---|---|---|---|---|---|---|---|---|
| DC Output | +3.3 V | + 5 V | +12 V (#1) | +12 V (#2) | +12 V (#3) | +12 V (#4) | -12 V | +5 Vsb |
| 20 A | 20 A | 37 A | n/a | n/a | n/a | 0.3 A | 2.5 A | |
| Individual Output | 32 A | 3.6 W | 12.5 W | |||||
| Rail Utilization | Sys | Sys | CPU & VGA | |||||
| Combined Output | 100 W | 444 W | ||||||
| Total Continuous Output | 450 W | |||||||
| Peak Output | n/a | |||||||
Seasonic’s X line is typically a top contender in our performance measurements. The less-expensive S12G still has something to prove, though. It does master our efficiency testing, according to the 80 PLUS specification, and even has a bit of room to spare.
At very low loads, the S12G’s efficiency is about the same as Corsair's RM450. At 25 W, it tails Cooler Master's V450S by about 10 percent. But in standby, without any load, Seasonic has the only PSU able to compete with the RM450 by demonstrating .05 W of consumption.
For those of you keeping score at home, that means this PSU hasn't exhibited any real weaknesses yet. The ripple and noise measurements continue along the same lines. There’s barely any ripple, and the curve is pretty smooth.
Thanks to its hybrid cooling solution, Corsair's RM450 just can’t be beaten when it comes to acoustics. Seasonic often triumphs in this metric. However, the company chooses not to use the dynamic cooling we've come to appreciate from its X family. That doesn't mean the S12G is loud. Quite the opposite. It's fan is on the quiet side, registering between 30.9 and 31.3 dB(A).
A Look at the PCB
There's no cable management, no hybrid fan control, and Seasonic sneaks in with the lowest price in today's story. Did the company have to cut some corners when it was picking components and putting the S12G together? Nope. We find a DC-to-DC converter topology with LLC, as well as a very good input filter including two X and six Y capacitors, three choke coils, and a MOV.
Hitachi supplies the primary capacitor. On the secondary side, there are a number of capacitors from the South Korean manufacturer Enesol, as well as a few by Chemi-Con and Rubycon. All in all, the parts are higher-quality than what we found from the other power supplies in our round-up. And then there’s the immaculate soldering work.
The bottom line is that Seasonic does everything right for a PSU in this price category for both component selection and build quality.
Configuration
| AC Source | Chroma Programmable AC Source 6530 |
|---|---|
| Power Meter | Yokogawa WT210 Digital Power Meter |
| Loads | 4x 600 W Chroma 63306 for 12 V Testing 4x 300 W Chroma 63306 for 5 and 3.3 V Testing Using Chroma High Speed DC Load Mainframes 6334 |
| Oscilloscope | Tektronix DPO3034 Digital Phosphere Oscilliscope (300 MHz) |
Methodology
| Voltages | 110 and 230 V |
|---|---|
| Standby Power | 0.25 A Fixed Current to Simulate PC Standby Power on 5 Vsb |
| 80 PLUS Efficiency Testing | 100/50/20% Load, Relative to Specified Total Output Load Distribution Across 12/5/3.3V Rails at the Same Proportion as Specified for 100% Testing at 110 V According to ATX 2.3 Specification |
| Efficiency at Fixed Loads | 25, 50, 85, 300, 500 W Loads Load Distribution across 12/5/3.3 V Rails at the Same Proportion as Specified for 100% |
| Peak Load Test | 110% Overload Testing at Maximum Combined 12 V |
| Temperature Test | Air Intake vs. Outtake Temperature Difference Tracking Highest Difference During All Tests |
Results
More measurement results for the PSUs in this round-up, as well as other PSUs, can be found in our Power Supply Charts.
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Enermax Revolutio...
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CoolerMaster V4505
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Corsair RM450
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Seasonic S12G 450W
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Power supplies in the 450 W range with 80 PLUS Gold certifications are understandably popular. They offer enough power for most PCs, they're obviously efficient, and they aren't incredibly expensive. Even though 450 W sounds small, a good manufacturer will arm its offering with plenty of cables and connectors (enough so that a couple of single-GPU graphics cards are often viable). Modular cables are almost always part of the value proposition as well.
Today's round-up shows that some of the top vendors make similar choices when it comes to pricing and the performance of their power supplies' internal parts. Differences that do exist typically involve the bundled accessories.
Because the companies that chose to submit samples for testing are generally well-respected, it's hard to go wrong with any of these units. Since we can't identify one clear winner, here are our thoughts on each power supply:
Enermax's 430 W Revolution X't has the lowest output rating in our round-up. However, the difference between it and the other three power supplies is small, especially since the Revolution's +12 V rail delivers up to 98% of its theoretical performance in practice.
Strengths include good build quality and lots of connectors. The partly modular cabling facilitates some flexibility. Performance-wise, our measurements turn out unremarkable; they're neither good or bad versus the competition.
If we look at Enermax's cooling solution, you get a constant, but unobtrusive fan noise. Compared to the rest of the field, however, it's the loudest. The components contained within aren't particularly high-end, though most enthusiasts would consider them acceptable.
All things considered, the Revolution X't does its job well. The worst thing we can say about it is that Enermax is on the expensive side in a field filled with strong contenders.
One such contender is Cooler Master's V450S. Fortunately for Enermax, you can't buy the V450S in the U.S. Overseas, where this power supply is available, it represents the semi-modular implementation of Cooler Master's completely modular V family. It shares that line-up's high efficiency, beating the other PSUs in our round-up at each load level. This distinction is particularly striking at low loads.
The V450S also does well when it comes to ripple and noise. The remaining measurements are unremarkable. Cooler Master does cut corners a bit on cable length and connector variety. As we saw from Enermax's Revolution X't, though, there’s nothing to complain about once we open the V450S up and pore over its internals.
If you're looking for a silent PSU, consider Corsair's RM450 instead. Its fan doesn’t even spin most of the time thanks to a well-designed semi-passive design. And even when higher loads necessitate active cooling, the fan is quiet.
The RM450’s build quality is exemplary, and its internals follow suit. You don't get the most modern topology, but since it still achieves 80 PLUS Gold-class efficiency, we can't really complain. But Corsair's RM450 doesn't push past those qualifying marks, and its efficiency drops fast at lower load levels.
One possible explanation could be the fully modular cabling, which is unique among the four power supplies tested today. Combined with long runs and a wide variety of connectors, you at least get the best possible flexibility for cable management.
At first glance, Seasonic's S12G 450 W appears to be this round-up’s wallflower. There's no cable management, the chassis isn't fancy, and the price tag is noticeably low. We know by now not to judge books by their cover though, right?
In reality, the S12G has every right to sport its 80 PLUS logo. Just like the Enermax and Corsair offerings, though, its efficiency does decline a lot faster than the Cooler Master V450S. Still, it doesn't exhibit any weaknesses in our other measurements, behaving well in the ripple and noise benchmarks.
Seasonic doesn't cut any corners with cable length or connector variety. The supply's fan does spin continuously, but it's also really quiet. Open the S12G up and, particularly after paying the lowest price in this round-up, you get your biggest surprise: a modern design with high-quality components and fantastic soldering throughout. Enthusiasts with their own cable management skills and a penchant for good bargains should choose this power supply.






































