by Dmitry Vasiliev
01/17/2012 | 02:21 AM
Power supply units with wattage ratings of 600 to 800 watts enjoy high demand nowadays. Even though the majority of home computers do not actually need that much power, no one is going to refuse to have a reserve of wattage, especially if you don’t have to pay much for it. So what can we expect from PSUs which offer that much wattage at a more or less affordable price? To answer this question we’ve taken half a dozen products, both new and not very new. All of them have one thing in common. Their price is more affordable compared to most other same-class PSUs.
The following article offers a detailed description of our testing methodology and equipment and a brief explanation of what the specified and tested parameters of power supplies mean: X-bit Labs Presents: Power Supply Units Testing Methodology. If you feel overwhelmed with the numbers and terms this review abounds in, refer to the Methodology.
You can also go to our Cases/PSU section to check out reviews of all other PSU models we have tested in our labs.
We will mark the actual power consumption of three system configurations (discussed in our article PC Power Consumption: How Many Watts Do We Need?) in the cross-load diagrams. This will help you see if the tested PSU can meet the requirements of a real-life PC.
We’ve tested a number of Chieftec PSUs in our labs and been generally pleased with them. We have rather high hopes about this one, too. It hails from the Nitro series which represents the top of the company’s current product line-up.
The BPS-650C is shipped in a rather small box of glossy cardboard. The packaging is unified for all BPS series products that range in wattage from 550 to 950 watts. The box has a plastic handle. Many manufacturers forget about this handy detail, but not Chieftec.
There is nothing extraordinary about the exterior design of this PSU. It is a standard-sized box with detachable cables and a large 140mm fan behind a wire grille.
There are small vent holes in one of the side panels. The other only has a stamped logo of the manufacturer. A label with specifications is on the bottom panel of the PSU. The dark-gray matte paint with shimmering metallic particles seems to be the most original feature in the exterior of this product.
Under the hood we can spot the familiar traits of the PSH platform Channel Well Technology. It is the newer, second version of it, though.
The differences from the original PSH platform can hardly be noticed with a naked eye, however. The component layout is largely the same whereas dedicated voltage regulation is still based on electromagnetic amplifiers.
The only visible difference from the first PSH is that there is only one daughter card here instead of two.
That single daughter card carries a PWM & PFC controller chip CM6800G.
The monitoring chip PS229, responsible for protection against various violations of electronic parameters, resides on the main PCB.
The PSU has electrolytic capacitors from United Chemi-Con at its output. KZE series capacitors enjoy an excellent reputation.
The Chieftec BPS-650C is equipped with the following cables and connectors:
Included with the PSU are:
The cables are sufficiently long, yet the 4+4-pin CPU power cable might have been made a little longer still to make sure that the PSU is compatible with large system cases that have a bottom PSU bay.
It can be noted that Chieftec has stretched the product unification idea to the limit: this model is only equipped with two graphics card cables although has as many as four connectors for them. The missing pair of cables might be useful, though, as the BPS-650C is quite capable of powering up a couple of performance-mainstream cards like GeForce GTX 560/560 Ti or Radeon HD 6870 in SLI or CrossFireX mode, respectively. At least its wattage meets GPU makers’ recommendations for such configurations. Each such card needs two 6-pin power connectors, so you won’t be able to connect two of them with the cables included with this PSU unless you use adapters.
The specifications are blameless and up to today’s standards. The BPS-650C can give you up to 636 watts across its solid +12V rail, its total output power being 650 watts. The load capacity of the +3.3V and +5V rails is quite high, too. The BPS-650C features 80+Bronze certification.
Working together with my APC SmartUPS SC 620, this PSU was stable at loads up to 385 watts when powered by the mains but could only switch to the UPS’s batteries at a load of 280 watts.
The +12V voltage is very stable. It mostly keeps within 1% of its nominal value and never exceeds the latter by more than 2%.
The +3.3V voltage is but slightly worse. It deflects by 3% from the required level at very high or very low loads on all of the power rails but is going to be within 2% under typical loads.
The +5V voltage can deviate to the permissible maximum of 5% but only when the overall load is greatly misbalanced towards the +5V rail. At typical loads of modern computers this voltage, just like the others, is not going to deviate more than 2%.
Thus, the BPS-650C delivers stable voltages, yet doesn’t feel quite confident at near-zero loads.
The high-frequency voltage ripple of this PSU is within the norm by some margin.
The voltage ripple is even weaker at the double frequency of the power mains.
The Chieftec BPS-650C is cooled by a 7-blade Yate Loon fan (D14BH-12, 2800 RPM, 140 mm). About one third of the impeller is covered with a piece of translucent plastic to optimize air flows.
The fan starts out at a rather high 1070 RPM, which is just comfortable enough, but keeps this speed until a load of 400 watts. Then the speed is increased linearly until full load. The top speed of the fan is about 1600 RPM.
The BPS-650C is somewhat below average in terms of noisiness, yet most people are going to be satisfied with it in this respect. The rather high start speed of the fan may disappoint users who value silence.
The power factor is high, just as you can expect from a power supply with active power factor correction. The efficiency is not record-breaking but meets the 80+Bronze requirements: 84.1% at 20% load, 86.9% at 50% load, and 84.8% at 100% load. The peak efficiency is 87.6% in the load range of 256 to 278 watts.
The standby source meets the requirements of the industry standard.
The Chieftec BPS-650C is a reasonably priced PSU with no obvious flaws. We could only note such downsides as the reduced number of graphics card cables included in the box and the somewhat short length of the CPU power cable. The rather high start speed of the fan (almost 1100 RPM) may also be a downside for some users. If you are not among them, and if you do not plan to build a SLI or CrossFireX configuration out of two graphics cards with two power connectors each, and if the 59cm CPU power cable is long enough for you, the BPS-650C is going to be a perfect buy.
In our previous review we were displeased with Cooler Master’s entry-level PSU from the Elite Power series as it turned out to be overpriced for its specs and to have an overstated wattage rating on its label. The GX series is positioned higher in the company’s product hierarchy and we’ve got its flagship 750-watt model. Let’s see if it can do better than its junior cousin.
The GX 750W comes in an even smaller box than the Chieftec BPS-650C. Besides the PSU, it contains a mains cord, mounting screws and a folded sheet of the installation guide.
The box is individual for each model of the series, differing from others in color and specifications you can read on its back.
The PSU resembles the Enhance ATX-0240GA model we’ve tested recently.
In fact, the GX 750W is identical to the mentioned model in everything including the black and smooth matte paint.
Enhance’s characteristic fingered heatsinks can be glimpsed through the punched out fan grid. So, we’ve identified the real maker of this PSU even before opening it up.
Although the GX 750W comes at the same price as the Chieftec BPS model discussed above, its circuit design is much simpler.
There is no dedicated voltage regulation here. The component density is lower. There are no modular cables.
There are Taicon and Su’scon capacitors at the output. Unfortunately, these components do not have a blameless reputation and are reported to fail sooner than expected.
The Cooler Master GX 750W is equipped with the following cables and connectors:
We’ve got a generous selection of peripheral power connectors here, particularly a SATA power connector sharing a cable with connectors of other types, but the CPU cable is obviously too short for a system case with a bottom PSU bay.
It is also rather odd for a 750-watt power supply to have only two graphics card connectors. [?????????, ????? ? ??????? 2 ?????? ? 2 ????????? ?? ?????? = 4 ??????? ?????] You can only need that much power for advanced graphics cards, but you won’t be able to connect more than a single top-end graphics card (or two mainstream ones with one power connector each) without using adapters with this PSU.
The specifications are good for a modern PSU. The GX 750W can deliver up to 95% of its full 750 watts across the +12V rail. This is as high as 720 watts. The combined load capacity of the +3.3V and +5V rails is 150 watts. The PSU claims to be able to cope with a short-term load of 900 watts. It is 80+Bronze certified.
Working together with my APC SmartUPS SC 620, this PSU was stable at loads up to 370 watts when powered by the mains but could only switch to the UPS’s batteries at 285 watts.
After the near-perfect performance of the Chieftec BPS in this test, the Cooler Master GX looks especially bad with its lack of dedicated voltage regulation.
The +12V voltage deviates very much at high loads on the +12V or the other rails. On the other hand, the deviation isn’t going to be higher than 3% with most real-life computer configurations.
The voltage on the +5V rail sags at high loads. As a result, the PSU cannot yield over 120 watts across the +3.3V and +5V rails combined without going beyond the permissible limits. In the typical load range this voltage is not going to deviate more than 2%, though.
The +3.3V voltage is good at low and medium loads, staying within 2% of the required level. It can go as far as 4% from that level at near-maximum loads, though.
So, the Cooler Master GX 750W is just satisfactory in terms of voltage stability, the only exception being the +5V rail. The PSU would lose the Power OK signal when there was a minimum load of 1 ampere on that rail, therefore we had to carry out our tests at a minimum load of 2 amperes. This must be a defect of the particular sample of the PSU, yet we have to report this disappointing fact.
The high-frequency voltage ripple is not strong, yet there are occasional voltage spikes above the permissible limits on the +3.3V and +5V rails. We’ve seen the same behavior with many other PSUs based on Seasonic’s entry-level platforms (and this Cooler Master PSU isn’t the worst among them, we should note).
The same goes for the low-frequency ripple except that the voltage spikes are not so high.
This PSU is cooled by a 7-blade Young Lin Tech fan (DFS122512H, 3000 RPM, 120 mm).
The fan starts out at a speed of 1000 RPM and maintains it until a load of 400 watts. Then it accelerates in a linear manner. The top speed is as high as 1500 RPM at full load. Having a smaller fan working at a lower speed, the Cooler Master turns out to be somewhat quieter than the above-discussed Chieftec but the fan’s behavior is overall the same.
The power factor is somewhat lower than what you can expect from a PSU with active power factor correction, but that’s not important for home users.
The efficiency is okay, too. The PSU meets the 80+Bronze requirements. Its efficiency was 86.7%, 87.6%, 82.2% at loads of 20%, 50% and 100%, respectively. Its peak efficiency was 88.6% at a load of 265 watts.
So, the Cooler Master GX 750W is highly efficient at low and medium loads but loses in efficiency at full load more than the above-discussed Chieftec does. The latter PSU was more consistent in this test.
The standby voltage is somewhat higher than necessary at any load, but meets the requirements of the industry standard.
The Cooler Master GX 750W is a rather quiet PSU with acceptable electrical parameters and a rich selection of peripheral power connectors. However, it offers only two graphics card connectors, which doesn’t seem enough for its wattage, and its CPU power cable is too short.
Lacking any special features, the NAXN series doesn’t stand out among Enermax’s products. We’ve got the most advanced and highest-wattage model, ENM850EWT, which has modular cables and 80+Bronze certification, but neither feature is something special nowadays.
The 750W model is actually the only one in the NAXN series to have the mentioned features. The rest of them, ranging in wattage from 350 to 600 watts, have non-modular design and basic 80+ certification at best. The two junior models even lack active PFC.
It is because the ENM850EWT comes from such a lusterless series that we want to cover it in this review. Otherwise, its price and wattage are higher than those of the other products tested here.
The ENM850EWT comes in a medium-sized glossy cardboard box which is the same for the two senior models of the NAXN series.
Besides the PSU, the box contains a pouch with manufacturer’s logo to keep the detachable cables in.
There’s nothing unusual in the exterior design of this product. We see a cute combination of a black case and a golden wire grid of the fan. The back panel is a honeycomb mesh.
The other side panels are blank, lacking any vent holes.
Enermax is known for original solutions but this particular product doesn’t come from a top-end series. Anyway, it features dedicated voltage regulation based on magnetic amplifiers: there are three rather than two chokes in the output circuitry area.
There are two small daughter cards installed on the main PCB. The one closer to the center carries a PWM and PFC controller.
The other, which is closer to the edge, carries a monitoring chip PS224.
The electrolytic capacitors at the output are manufactured by Teapo; a large one from Rubycon is installed at the input.
The Enermax NAXN ENM850EWT is equipped with the following cables and connectors:
Included with the PSU are:
The selection of connectors is sufficient. The main cables are long enough but the connectors of the peripheral cables are placed rather too close to each other.
You can see that the NAXN ENM850EWT is not a very advanced PSU by looking at its specs. It can yield 100 watts less than its full load across the +12V rail, which is not typical of today’s top-end PSUs. The load capacity of the +3.3V and +5V rails is exceedingly high by today’s standards at 180 watts. This is 3 or 4 times as high as a modern computer actually needs.
The peak output power is declared to be 10% higher than the continuous one for this PSU series. It means 935 watts for the NAXN ENM850EWT model.
The PSU features 80+Bronze certification which guarantees 82% efficiency at 20% and 100% load and 85% efficiency at 50% load.
Working together with my APC SmartUPS SC 620, this PSU was stable at loads up to 370 watts when powered by the mains but could not switch to the UPS’s batteries even at a load of 280 watts.
The +5V and the crucial +12V rail are both stable, their voltages staying within 3% of the required levels. The difference is proportional to load: the higher the load, the smaller the difference between the actual and nominal voltage level.
The +3.3V voltage is somewhat worse as it deflects from 3.3 volts sharp by 4% when there is low load on all of the power rails. Otherwise, the diagram is similar to those for the other voltages.
All in all, the NAXN ENM850EWT delivers very stable voltages.
The +12V rail has clearly defined high-frequency voltage ripple, but it is very weak. The voltage ripple on the +3.3V and +5V rails is almost nonexistent.
The same goes for the low-frequency output voltage ripple.
The NAXN ENM850EWT is cooled by an 11-blade Globe Fan (RL4Z B1352512H, 1500 RPM, 135 mm). Notwithstanding its transparent impeller, the fan lacks highlighting.
Mechanical noises could be heard at low speeds of the fan, but at high speeds it only produced pure aerodynamic noise.
The fan starts out at a speed below 850 RPM and keeps it until a load of 300 watts. The speed grows linearly afterwards, reaching the subjectively comfortable limit of 1000 RPM at a load of 450 watts. The fan is rotating at 1400 RPM at full load, which is lower than the top fan speed of most other PSUs.
The NAXN ENM850EWT is somewhat better than most other PSUs in terms of noisiness. A special feature of this PSU is that its fan keeps on rotating at a low speed for a while after the PSU has been shut down. This helps cool the components better.
The power factor is somewhat inferior to that of most PSUs with active power factor correction.
The efficiency is far from record-breaking but meets the 80+Bronze requirements by some margin. The NAXN ENM850EWT was 85%, 87.7% and 84.7% efficient at the three reference loads (20%, 50% and 100%, respectively). Its peak efficiency was 88.1% at a load of 384 watts.
The standby voltage is always higher than necessary but meets the requirements of the industry standard.
The NAXN ENM850EWT lacks any extraordinary features but also has no obvious downsides. It is rather quiet and can make a good buy if you’re satisfied with its price.
Although this review is supposed to cover 600W and higher PSUs, it wouldn’t be right to dismiss the 550W EVO Blue. It is just very similar to its 750W cousin.
Both are shipped in identical large boxes. The only difference is the paper belt where the wattage rating of the specific model is indicated.
You can learn specifications of the different models of the series on the back of the box. The text in several languages confirms that there is indeed a power supply, rather than something else, inside the box.
The accessories in the box include a vibration-absorbing silicone pad the PSU can be installed on. The EVO Blue series isn’t new, yet can still be found selling in shops, so you may be interested in learning how it performs.
If you are bored with conventionally designed PSUs whose only difference from others is a sticker with the manufacturer’s name, Thermaltake’s EVO Blue series is going to be a nice diversion. The two models look the same (except for the wattage rating and specs) but both are highly original.
There is a lot of vent openings all over the PSU case, including the horizontal slits opposite the fan that we first saw with the ToughPower QFan 650 A. This solution is hardly efficient, though.
There is a vent grid even in the bottom panel of the case which is usually blank. It only serves a decorative purpose, though. Besides the effective appearance of the PSU at large, its fan has as many as five selectable highlighting modes you can switch through with the button on the back panel.
The highlighting can be blue, green or red. There are also two more modes that alternate between the available colors in different order. The highlighting can be turned off altogether. The modular connectors are highlighted as well, in constant blue.
So, Thermaltake’s EVO Blue series looks like a modder’s dream. Hopefully, the rest of its characteristics are going to be that spectacular, too.
We’ve already noted some outward similarity between the EVO Blue series and the ToughPower QFan 650 A. The circuit design turns out to be similar, too.
The PSU is based on Channel Well’s PSH platform which is known to us by lots of other PSUs selling under various brands.
A PWM and PFC controller CM6800X resides on a separate card located near the middle of the main PCB.
We won’t describe the well-known platform once again. We can only remind you that it features dedicated voltage regulation based on electromagnetic amplifiers. Thermaltake’s implementation has Teapo capacitors at the output.
The EVO Blue 550W is equipped with the following cables and connectors:
Included with the PSU are:
The EVO Blue 750W model has a third connector on each SATA cable. It also comes with a second graphics card cable with an 8-pin connector and an 8->6-pin adaptor for it.
We like the cables of these PSUs. Those of them that should be long (the mainboard and CPU ones) are indeed long whereas the rest of the cables are just the right size (too long peripheral cables may be unhandy).
On the other hand, we can see one problem about the cables. The number of SATA connectors is too small for a 550-watt PSU. It is almost impossible to connect more than two HDDs together with an optical drive. Why not include two SATA cables with three connectors on each, as with the 750W model? The accessories to the 550W model are not so scanty, so why did they try to save on the cables?
Like with the Chieftec PSU, this may be due to unreasonable unification. For example, the number of the junior EVO Blue model’s connectors for graphics card cables does not match the number of included cables (this solution can be explained by the rather low wattage rating of this model, though).
Rather disappointingly, the declared 550 and 750 watts are just the peak output power whereas the continuous one is 50 watts lower for each model. The load capacity of the junior model’s +12V rail is not very high: up to 432 watts or 86.4% of full output power. The +3.3V and +5V rails can deliver 140 watts, which is more than enough for any modern computer.
The senior model differs in the load capacity of its +12V rail which is 20 amperes higher. Thus, it can deliver 672 out of its full 700 watts across the +12V rail. This is high enough (96%) for a modern PSU.
The EVO Blue series is not 80+ certified but Thermaltake claims them to be 78% or more efficient with 115V mains and 80% and more efficient with 230V mains.
Working together with my APC SmartUPS SC 620, the EVO Blue 550W was stable at loads up to 375 watts when powered by the mains but could not switch to the UPS’s batteries even at 280 watts. The senior model was stable at 375 and 315 watts when powered by the mains and the UPS’s batteries, respectively.
We have to use animated diagrams for the sake of readability here. Otherwise, there would be too many pictures in this section. It is clear from the diagrams below that the junior model is inferior to the senior one in terms of voltage stability.
Well, the junior model isn’t so bad after all. Its voltages do not deflect more than 3% from the required levels in the typical load range.
But the senior model is better. The voltages are within 2% of the required levels in the typical load range and within 3% at any loads.
It must be noted that both EVO Blue series models were not very confident at zero loads, losing the Power OK signal.
It is the output voltage ripple that’s the main downside of both Thermaltake PSUs. As if to make up for the previous test it has passed very well, the 750W model is especially bad here. Its output voltage ripple largely fits within the requirements of the industry standard but there are a lot of voltage spikes that go beyond the permissible limits.
The junior model has too high voltage spikes as well, but they are not as frequent and high as those of the senior model.
The same goes for the voltage ripple at the double frequency of the power mains. The senior model has stronger pulsations.
Each of these PSUs is cooled with a 7-blade 140mm fan labeled as TT-1425. The real maker’s name is printed in small letters. It’s Hong Sheng.
So, the senior model keeps the fan speed at the same level until a load of 330 watts. Then the fan quickly accelerates, reaching 1700 RPM at 600 watts. This speed is then maintained until full load.
The junior model speeds its fan up sooner, at a load of 200 watts, but reaches the same top speed of 1700 RPM at full load.
Alas, neither of these PSUs can be called quiet. They are just average in terms of noisiness.
The efficiency of the PSUs is just what we can expect after tests of other products based on the Channel Well PSH platform.
The manufacturer’s claims about the efficiency of these PSUs are well-grounded. Starting from a load of 100 watts, each of them is 80% or more efficient with our 230V mains. That’s no record-breaking performance but the result good nonetheless. The efficiency graph goes close to 84% through most of the diagram, lowering to 83% and 81.2% at full load with the junior and senior models, respectively.
The power factor is typical of PSUs with active power factor correction.
The two models have almost the same result in this test. Their standby source copes with its job well enough.
We guess the key advantage of Thermaltake’s EVO Blue series is its exterior design. The good results in the cross-load test are a secondary advantage. The downside is that these PSUs are based on an outdated platform. They are not very quiet and have some problems in terms of their electric parameters. Perhaps they will be appreciated by some modders.
Power supplies are not the type of product Vantec has earned its reputation with. But the company has come to the highly competitive PSU market like many other PC component makers that have not been into PSUs before.
The ION2+ VAN-600AS comes in a rather large and neat box made of matte cardboard. The box has a carry handle.
The product’s key features and connectors are listed on the back of the box. The packaging is individual for this particular PSU model.
The exterior design of this PSU is quite conventional.
The case is painted black and has modest dimensions. The large fan under a wire grid is painted the color of the case. A Vantec logo can be seen in the middle of the grid. The back panel is a honeycomb mesh.
The PSU has four connectors for detachable power cables. Otherwise, there are no openings for ventilation in its side panels.
The interior of the ION2+ VAN-600AS looks familiar to us. It is the Andyson Performance F series platform we know from our review of the Hiper M600.
The key differences boil down to the four connectors for detachable cables located on a separate card (the small main PCB allows to accommodate the modular cable system without changing the dimensions of the PSU case) and to the shape of the heatsinks which are larger here compared to other Andyson-based PSUs and resemble the monumental heatsinks of Enhance's platforms.
Delving into smaller details, we can note the transparent protective plate in the output area and the different capacitors.
The Hiper M600 had Teapo capacitors at the output and a JunFu “barrel” at the input whereas the Vantec ION2+ VAN-600AS employs Teapo capacitors both at the input and output and also has WG and some low-capacitance JunFu components.
The Vantec ION2+ VAN-600AS is equipped with the following cables and connectors:
Included with the PSU are:
The main cables are too short. This PSU is not going to be a good choice for system cases with a bottom PSU bay. The selection of available connectors is not rich, yet sufficient for a PSU of that wattage.
The Vantec ION2+ VAN-600AS specifications are absolutely identical to those of the Hiper M600, the two PSUs being based on the same platform. So, we can note the same downside: the load capacity of the +12V rail is rather low at only 72% of the PSU’s full output power.
As opposed to the original Andyson platform, the Vantec has only basic 80+ certification rather than 80+Bronze.
Working together with my APC SmartUPS SC 620, this PSU was stable at loads up to 385 watts when powered by the mains and could switch to the UPS’s batteries at a load of 295 watts.
While the Hiper M600, based on the same platform, performed more or less well in this test, the Vantec's cross-load characteristics are much worse.
The +12V voltage is too unstable when there is high load on the +3.3V and +5V rails.
The +3.3V voltage, which was almost immaculate with the Hiper M600, sags heavily when the load on the +12V rail grows up but does not go beyond the permissible limits.
The +5V voltage seems to be the worst one as it sags quickly as the load grows up. As a result, the PSU is unable to deliver over 70 watts across its +3.3V and +5V rails combined while keeping the voltages within the required ranges.
Thus, the Vantec ION2+ VAN-600AS is no more than just satisfactory in this test.
The picture is similar to what we saw with the Hiper M600. The high-frequency voltage ripple is largely within the norm, but there are occasional voltage spikes above the permissible limits.
The same goes for the voltage ripple at the double frequency of the power mains.
The PSU is cooled by an 11-blade 135mm Young Lin Tech fan (DFS132512H, 1700 RPM). About one fourth of the impeller is covered with a transparent piece of plastic that helps optimize air flows.
The fan starts out at a rather low speed of less than 800 RPM but doesn’t keep it for long. The fan begins to accelerate somewhat later than the Hiper M600's fan (at a load of 250 rather than 200 watts) and its top speed is somewhat lower at 1550 RPM.
The power factor is lower than average if compared to other PSUs with active power factor correction, but much higher than that of the Hiper M600 which was surprisingly poor in this test.
The Vantec ION2+ VAN-600AS is inferior to the Hiper M600 in efficiency, though. The latter, lacking 80+ certification, turned out to meet the 80+Bronze requirements Andyson’s native PSUs are certified for whereas the Vantec can only meet the basic version of that industry standard. This agrees with the manufacturer's specs, however.
The standby source copes with its job just fine. This voltage doesn't go out of the limits prescribed by the industry standards.
The Vantec ION2+ VAN-600AS can only be praised for its low noise level and good efficiency at low and medium loads. Otherwise, it is all about downsides. Its +12V rail is unstable; its +5V voltage is prone to go out of the prescribed range; its efficiency falls at high loads; its output voltage ripple is too strong; and it uses capacitors of dubious quality.
The products from Chieftec and Enermax stand out among the half-dozen power supplies we have tested in this review. Both feature handy modular design and meet the 80+Bronze requirements. Their other electrical parameters are good, too, and they are quiet enough, especially the Enermax. However, the Enermax NAXN ENM850EWT is considerably more expensive, so the Chieftec BPS-650C may look like a better buy in terms of price/performance ratio.
The Cooler Master GX 750W is somewhat inferior to the pair of leaders. It cannot boast modular design and its voltages are not so stable due to the lack of dedicated regulation. It also has too few graphics card connectors for its wattage. On the other hand, it is the quietest PSU in this review, together with the Enermax.
Thermaltake’s EVO Blue series is based on the outdated Channel Well PSH platform. That’s why their efficiency isn’t high by today’s standards. These products can make up for their downsides with their eye-catching exterior design if you value the latter as highly as the superior technical and acoustic parameters of the more up-to-date PSUs.
The Vantec ION2+ VAN-600AS is the worst product of this review. It is inferior in almost every aspect to the Hiper M600 which is based on the same platform and was itself far from brilliant in our previous test session. Perhaps the Andyson Performance F platform is far from perfect, yet the ION2+ VAN-600AS is surely not the best implementation of it.