Original Link: https://www.anandtech.com/show/12070/the-corsair-tx550m-80plus-gold-psu-review
The $80 Power Supply for Almost Everyone: The Corsair TX550M 80Plus Gold PSU Review
by E. Fylladitakis on December 1, 2017 8:00 AM EST- Posted in
- Corsair
- PSUs
- Cases/Cooling/PSUs
- 550W
- TX
- Modular
- Power Supply
Corsair started off as a high-performance computer memory manufacturer, but they evolved into one of the largest and most recognizable companies in the consumer PC market. Today the company markets an immense variety of products, including practically everything short of motherboards and processors. One of their most popular product ranges is that of power supply units (PSUs). The company released their first few PSUs back in 2006 but today they are offering a vast variety of products for every kind of user and application.
A few weeks ago we had a look at the HX850, one of Corsair’s better PSUs, a product designed for advanced gaming/workstation systems. Impressive as it was, its power output (and price tag) undoubtedly was excessive for the average home user and casual gamer. With PSUs, bigger is not better; using a PSU that is excessively overpowered will force it to operate well outside its optimal loading range, effectively reducing its efficiency and performance.
The optimal power range for a typical home entertainment/gaming system usually is within 400-600 Watts. To that end, Corsair supplied us with the TX550M, a PSU that the company feels it is ideal for the mainstream gamer.
Power specifications ( Rated @ 50 °C ) | |||||
AC INPUT | 100 - 240 VAC, 50 - 60 Hz | ||||
RAIL | +3.3V | +5V | +12V | +5Vsb | -12V |
MAX OUTPUT | 25A | 20A | 43A | 3A | 0.8A |
120W | 516W | 15W | 9.6W | ||
TOTAL | 550W |
On paper, it certainly does look that way - it has the ideal power output for a single-GPU card gaming system, impressive performance specifications, a 7-year warranty, and a very reasonable ($80) price tag.
Packaging and Bundle
We received the TX550M in a cardboard box that was peculiarly small in comparison to that of other Corsair products. Still, the cardboard box is strong enough to protect the PSU during shipping. The artwork is based on the same yellow/black that Corsair has been using for the past several years, with a picture of the PSU being the focus of it at the front of the package. A lot of information is printed on the sides and rear of the box.
The bundle of the TX550M is unsurprisingly simple. Inside the box we found only the typical AC power cable, black 3M mounting screws, a standard manual, a case badge, and a few short cable ties. Corsair does not supply any thumbscrews, cable straps, or other accessories.
The TX550M is a semi-modular PSU, meaning that the basic 24-pin ATX and 4+4 pin CPU power cables are hardwired to the unit but the rest of the cables are removable. All of the modular cables are flat, ribbon-like, with all-black wires and connectors. The same goes for the 4+4 pin CPU power cable that is hardwired to the unit. The 24-pin ATX cable is an exception, with all-black wires that are wrapped inside a classic black nylon sleeve.
Corsair TX550M | ||
Connector type | Hardwired | Modular |
ATX 24 Pin | 1 | - |
EPS 4+4 Pin | 1 | - |
EPS 8 Pin | - | - |
PCI-E 6+2 Pin | - | 2 |
PCI-E 8 Pin | - | - |
SATA | - | 5 |
Molex | - | 4 |
Floppy | - | 1 |
Recent Power Supply Reviews
AnandTech tests a good number of power supplies each year, mostly in the popular power ranges (650-850W) with a few reviews now-and-again for small form factor parts or larger behemoths. Here are the power supplies we have reviewed in the last twelve to eighteen months.
- [link] The Corsair TX550M 80Plus Gold PSU Review (this review)
- [link] The Corsair HX850 80Plus Platinum PSU Review
- [link] The Seasonic PRIME Titanium PSU (650W, 750W, 850W) Review
- [link] The Riotoro Onyx Power Supply Review: 650W & 750W Tested
- [link] The BitFenix Whisper M 450W & 850W PSU Review
- [link] The Silverstone ST30SF & ST45SF SFX Power Supply Review
- [link] The Zalman ZM1200-EBT 1200W Power Supply Review
- [link] The Be Quiet! SFX-L Power 500W PSU Review
- [link] The Enermax Revolution SFX 650W PSU Review
- [link] The SilverStone SX700-LPT SFX 700W PSU Review
External Appearance
The TX550M is the least powerful model of the entire TX series. It is aesthetically simple and subtle, with the designer trying to find a balance between oversimplification and excessiveness. The chassis is sprayed with a satin black paint and decorative stickers cover the largest portion of its sides. These decorative stickers have the company logo and product model printed on them, and are placed in such a way that the sticker facing the right side of a case will always be upright, regardless whether the PSU has been installed with its cooling fan facing upwards or downwards. The sticker with the electrical specifications and certifications of the PSU can be found at the top side of the chassis.
With a body that measures 150 × 86 × 140 mm (5.9 × 3.4 × 5.5 in), the TX550M adheres fully to the ATX design guide, making it compatible with any ATX-compliant case. The design holds no surprises. At the rear we can see the typical AC receptacle and a small on/off switch, while at the front we find the four connectors for the modular cables and the hardwired cables. There are four connectors, three for Molex/SATA cables and one for a CPU/PCIe cable. Note that only the PCIe cable with the two 6+2 pin connectors is included in the original bundle. Still, if the user wants to power a system that requires two 4+4 pin CPU cables but has no PCIe connectors at all, it is possible to do so with a TX550M.
Internal Design
Due to its standard ATX chassis, the largest fan that Corsair could fit in the TX550M is a 120 mm NR120L. Corsair rebrands their fans and we cannot tell who the original manufacturer is but we can tell it has a rifle (advanced sleeve) bearing engine and a maximum speed of about 1500 RPM. The design of the blades suggests that it is a very high-pressure fan, which appears to be a strange selection for a PSU without excessively packed internals.
The OEM behind the creation of the TX550M is a Chinese OEM, Great Wall. We first encountered Great Wall’s designs when Corsair first implemented their platforms back in 2011. Great Wall is not a very popular OEM but they frequently cooperate with Corsair and their products were proven to be reliable.
The filtering stage of the TX550M begins on a small PCB soldered at the back of the AC receptacle and continues onto the main PCB. We counted a total of four Y capacitors, two X capacitors and two filtering inductors, which are the standard for a quality PSU. There is one conversion bridge feeding the APFC circuitry. Surprisingly, the 550W unit has two APFC capacitors, each rated at 450V/220μF. Great Wall could easily replace these two small capacitors with an equally effective larger one. The APFC coil is shielded inside a plastic casing, most likely to prevent electromechanical noise (also known as “coil whine”).
Generally speaking, the platform of the TX550M is technologically simple, based on circuitry designs that are being used into consumer PSUs for many years. Two MOSFETs form the simple half-bridge primary inversion circuitry and four MOSFETs generate the 12V line on the secondary side of the main transformer. The DC-to-DC converters found on the vertical PCB generate the minor 3.3V and 5V rails. It would seem that the PSU owes its 80Plus Gold efficiency rating to the use of highly efficient active components, as we have seen other units using the same base platform with minimal differences failing to reach such high efficiency standards.
All of the capacitors inside the TX550M are coming from Japanese manufacturers. The primary APFC electrolytic capacitors are from Nippon Chemi-Con. The secondary capacitors, electrolytic and polymer alike, are supplied by Nippon Chemi-Con or Rubycon. Both manufacturers are considered to be two of the most reliable manufacturers and are highly popular. The heatsinks of the PSU appear to be adequate for an 80Plus Gold certified PSU but they could definitely be much better.
Cold Test Results
For the testing of PSUs, we are using high precision electronic loads with a maximum power draw of 2700 Watts, a Rigol DS5042M 40 MHz oscilloscope, an Extech 380803 power analyzer, two high precision UNI-T UT-325 digital thermometers, an Extech HD600 SPL meter, a self-designed hotbox and various other bits and parts. For a thorough explanation of our testing methodology and more details on our equipment, please refer to our How We Test PSUs - 2014 Pipeline post.
The latest revision of the TX-M series is certainly improved in terms of efficiency, yet it still fails to achieve >92% at half load with an input voltage of 230 VAC. This result, however, does not mean that the unit’s certifications are false, just that it received its efficiency rating with an input voltage of 110 VAC, under which the 80Plus directive is slightly more lenient.
This particular model’s efficiency certification can be viewed here. The vast majority of manufacturers submit their units for 110 VAC testing - only 5% of the 80Plus certified non-redundant PSUs have been tested with an input voltage of 230 VAC. The TX550 maintains a good average efficiency of 90.3% within its nominal load range (20% to 100% of the unit's capacity) but tends to favor medium-to-heavy loads, struggling when the load is lower than 200 Watts.
The thermal control scheme of the Corsair TX550M is very simplistic, with the fan adjusting its speed according to the internal temperature of the unit. As such, it manages to maintain very low noise levels while at room temperature and up to medium loads. At heavier loads, the fan will increase its speed, yet not overly so, maintaining audible but typically comfortable noise levels.
Hot Test Results
We can see in the following tables that the electrical performance of the Corsair TX550M is very good for a mid-range PSU. Corsair definitely improved Great Wall’s designs vastly since our last encounter with them, increasing the efficiency and power quality of the platform. Although it does not impress, the maximum ripple of 36 mV on the 12V line under maximum load is a good power quality figure and satisfactory considering the price range of the PSU.
Main Output | ||||||||
Load (Watts) | 111.24 W | 277.4 W | 413.29 W | 549.67 W | ||||
Load (Percent) | 20.22% | 50.44% | 75.14% | 99.94% | ||||
Amperes | Volts | Amperes | Volts | Amperes | Volts | Amperes | Volts | |
3.3 V | 2.26 | 3.34 | 5.66 | 3.33 | 8.49 | 3.31 | 11.32 | 3.3 |
5 V | 1.81 | 5.08 | 4.53 | 5.07 | 6.79 | 5.02 | 9.06 | 5 |
12 V | 7.79 | 12.13 | 19.47 | 12.1 | 29.21 | 12.02 | 38.95 | 11.99 |
The TX550M appears to be a little sensitive to heavy cross-loading, with the maximum ripple on the 12V line jumping to 52 mV, but that still is a good performance figure under a highly unlikely usage scenario. The voltage regulation on every voltage line is between 1.2% and 1.4%, which is very good by today’s standards.
Line | Regulation (20% to 100% load) |
Voltage Ripple (mV) | |||||
20% Load | 50% Load | 75% Load | 100% Load | CL1 12V |
CL2 3.3V + 5V |
||
3.3V | 1.4% | 16 | 16 | 18 | 22 | 16 | 20 |
5V | 1.5% | 20 | 20 | 22 | 24 | 18 | 24 |
12V | 1.2% | 22 | 26 | 30 | 36 | 52 | 34 |
High ambient temperatures have a measurable, but not excessive or unexpected, impact on the electrical performance of the Corsair TX550M.
The average nominal load range (20%-100%) efficiency drops by 0.7%, down to an average of 89.6%, when in a warm environment. This drop is evenly distributed across the load range, suggesting that there are no component quality or thermal stress issues. Note that the TX550M still is significantly more efficient when handling loads greater than 250 Watts.
The thermal control of the Corsair TX550M is simplistic, setting the speed of the fan mainly according to the internal temperature of the unit. Inside our hotbox, the high internal temperatures of the PSU force the fan to almost instantly reach an audible, yet typically comfortable noise level. From that point onwards, the speed of the fan is increasing almost linearly along with the load but, surprisingly, it does not ever reach painfully high noise levels. It will surely be loud at maximum load under such conditions, but we usually expect much higher noise levels from PSUs around this price range. Considering the very high ambient temperature, the internal temperature of the TX550M is good, although there definitely is room for improvement.
Conclusion
With the TX-M series, Corsair is trying to fill the gap between its low-cost products and the high performance HX/AX series. The TX-M PSUs are designed to entice the average user who wants something better than a basic model, yet without having to break the bank in order to obtain it. Today we reviewed the least powerful model of the series, the TX550M. As its name implies, the TX550M has a maximum power output of 550W, which is more than adequate for typical single-GPU gaming/workstation systems. It is rated for continuous operation at 50°C and comes with an 80Plus Gold efficiency certification.
The Corsair TX550M is based on a platform by Great Wall, a Chinese OEM, which Corsair has been cooperating with for several of their PSUs over the past few years. This is the most advanced version of this platform that we have seen to this date, boosting the efficiency (just) enough for the PSU to earn an 80Plus Gold efficiency certification. Corsair’s optimizations did not stop there, as their engineers also managed to significantly improve the power quality of the PSU, resulting to low ripple/noise levels for a PSU of this class. The voltage regulation also is very good. Overall, the electrical performance of the TX550M is excellent for a “mainstream” PSU.
On the other hand, the thermal performance could use a few upgrades. The TX550M is neither too hot or too loud - just unsophisticated. Its thermal control feels archaic by today’s standards, when it could have a more powerful fan paired with a start/stop function, allowing it to operate fanless when possible but also keep the temperatures low when needed. The TX550M however is using the fan all the time, even when it does not really need to, making the PSU audible when it could be entirely quiet. On the other hand, the mediocre fan can barely provide enough airflow to maintain safe operating temperatures under adverse environmental conditions. Overall, the thermal control of the TX550M certainly works, but it could do much better.
Aesthetics are a subjective matter, but making the TX series aesthetically unique or attractive clearly was not Corsair’s focus. Unlike the more expensive PSUs of the company, the TX-M does not feature a custom chassis with chamfered edges and other aesthetic improvements. It is using a typical ATX steel chassis, with its only aesthetic improvements being a matte black paint and a semi-modular design. In terms of quality, Corsair is using components only from renowned manufacturers and we also found the assembly job of the TX550M to be excellent. It is no chance that the company is covering the latest TX-M units with a seven year warranty. The TX550M is a PSU designed to reliably serve for many years.
Summing up the above, the TX550M is a very reliable PSU with good electrical performance, making it an ideal choice for users who want to power a typical single GPU gaming/workstation system and have no need for extra/exotic features. Its current retail price of $80 is reasonable, yet it can be frequently found on sale for less than $70 (the 650W version is on sale for $74 at the time of this review), offering an outstanding value-to-performance ratio and long-term reliability.