Tom's Hardware Verdict
The Asus TUF Gaming 550W belongs to the upper end of the budget PSU category. It is identical to the highly popular Corsair CX550, the one made by Great Wall, which the less advanced CX550M replaced.
Pros
- +
Full power at 40 degrees Celsius
- +
Good overall performance
- +
Efficient
- +
Tight load regulation on the minor rails
- +
Low ripple
- +
Not noisy under normal operating conditions
- +
Alternative Low Power Modes support
- +
Good soldering quality
- +
Double ball-bearing fan
- +
(Very) long EPS cable
- +
Adequate distance between the 4-pin Molex connectors
- +
6-year warranty
Cons
- -
Very short hold-up time
- -
Mediocre transient response
- -
High inrush currents
- -
High OCP triggering points on the minor rails
- -
Lelon caps everywhere
- -
Low PF with 230V
- -
12V Voltage drop during the turn-on transient tests
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The ASUS TUF Gaming 550W Bronze is a budget-oriented PSU that manages to achieve high-performance thanks to the modern platform that it uses. Nevertheless, the competition is rough. Although units like the XPG Pylon 550, Corsair CX650M, and Thermaltake Smart BM2 550 use less-advanced platforms, they still take the lead in overall performance, leaving no room for the TUF Gaming 550 to earn a place in our best PSUs article.
The TUF-Gaming series consists of four PSU models with capacities ranging from 450W to 750W. The model we are evaluating here has 550W max power, ideal for a a small home PC with a mid-end GPU or a business-oriented PC with an embedded GPU. To keep the production cost low, ASUS used a non-modular but modern design provided by Great Wall. This is the same platform found in the Corsair CX line, which has been replaced by the CX-M line that might utilize a semi-modular design but also uses a less advanced platform than CX.
The TUF 550 is 80 PLUS Bronze, and Cybenetics Silver certified in efficiency. In noise, it received a Cybenetics Standard++ rating, which is not so flattering for a low-capacity PSU, especially one using a modern platform. Its dimensions are standard, with 150mm depth, allowing the installation of a 135mm fan.
Specifications of Asus TUF Gaming 550W
| Manufacturer (OEM) | Great Wall |
| Max. DC Output | 550W |
| Efficiency | 80 PLUS Bronze, Cybenetics Silver (85-87%) |
| Noise | Cybenetics Standard++ (30-35 dB[A]) |
| Modular | ✗ (fixed) |
| Intel C6/C7 Power State Support | ✓ |
| Operating Temperature (Continuous Full Load) | 0 - 40°C |
| Over Voltage Protection | ✓ |
| Under Voltage Protection | ✓ |
| Over Power Protection | ✓ |
| Over Current (+12V) Protection | ✓ |
| Over Temperature Protection | ✓ |
| Short Circuit Protection | ✓ |
| Surge Protection | ✓ |
| Inrush Current Protection | ✓ |
| Fan Failure Protection | ✗ |
| No Load Operation | ✓ |
| Cooling | 135mm Double Ball-Bearing Fan (CF1325H12D) |
| Semi-Passive Operation | ✓ |
| Dimensions (W x H x D) | 150 x 85 x 150mm |
| Weight | 1.92 kg (4.23 lb) |
| Form Factor | ATX12V v2.53, EPS 2.92 |
| Alternative Low Power Mode (ALPM) compatible | ✓ |
| Warranty | 6 Years |
Power Specifications: Asus TUF Gaming 550W Bronze
| Rail | Row 0 - Cell 1 | 3.3V | 5V | 12V | 5VSB | -12V |
| Max. Power | Amps | 25 | 20 | 45.8 | 3 | 0.8 |
| Row 2 - Cell 0 | Watts | Row 2 - Cell 2 | 120 | 549.6 | 15 | 9.6 |
| Total Max. Power (W) | Row 3 - Cell 1 | Row 3 - Cell 2 | 550 | Row 3 - Cell 4 | Row 3 - Cell 5 | Row 3 - Cell 6 |
Cables & Connectors for Asus TUF Gaming 550W
| Captive Cables | Row 0 - Cell 1 | Row 0 - Cell 2 | Row 0 - Cell 3 | Row 0 - Cell 4 |
| Description | Cable Count | Connector Count (Total) | Gauge | In Cable Capacitors |
| ATX connector 20+4 pin (610mm) | 1 | 1 | 18-20AWG | No |
| 4+4 pin EPS12V (820mm) | 1 | 1 | 18AWG | No |
| 6+2 pin PCIe (610mm+100mm) | 1 | 2 | 18AWG | No |
| SATA (400mm+110mm+110mm) | 1 | 3 | 18AWG | No |
| SATA (410mm+110mm) | 1 | 2 | 18AWG | No |
| 4-pin Molex (400mm+150mm+150mm+150mm) | 1 | 4 | 18AWG | No |
| Modular Cables | Row 8 - Cell 1 | Row 8 - Cell 2 | Row 8 - Cell 3 | Row 8 - Cell 4 |
| AC Power Cord (1390mm) - C13 coupler | 1 | 1 | 18AWG | - |
Given its capacity, the PSU has enough cables and connectors. On top of that, the cables are long, especially the EPS, which reaches 810mm! Lastly, the distance between the 4-pin Molex connectors is adequate at 150mm.
Component Analysis of Asus TUF Gaming 550W
We strongly encourage you to have a look at our PSUs 101 article, which provides valuable information about PSUs and their operation, allowing you to better understand the components we're about to discuss.
| General Data | - |
| Manufacturer (OEM) | Great Wall |
| PCB Type | Single Sided |
| Primary Side | - |
| Transient Filter | 4x Y caps, 2x X caps, 2x CM chokes, 1x MOV |
| Inrush Protection | NTC Thermistor 15S1R5M (1.5 Ohm) |
| Bridge Rectifier(s) | 1x GBU15K (800V, 15A @ 100°C) |
| APFC MOSFETs | 2x ROHM R6020ENX (600V, 20A, Rds(on): 0.196Ohm) |
| APFC Boost Diode | 1x NXP BYC8B-600 (600V, 8A) |
| Bulk Cap(s) | 1x Lelon (450V, 330uF, 2,000h @ 105°C, LSG) |
| Main Switchers | 2x STMicroelectronics STF24N60DM2 (600V, 11A @ 100°C, Rds(on): 0.2Ohm) |
| APFC Controller | Champion CM6500UNX & CM03AX |
| Resonant Controller | Champion CM6901X |
| Topology | Primary side: APFC, Half-Bridge & LLC converter Secondary side: Synchronous Rectification & DC-DC converters |
| Secondary Side | - |
| +12V MOSFETs | 4x Advanced Power AP9990GP (60V, 80A @ 100°C, Rds(on): 6mOhm) |
| 5V & 3.3V | DC-DC Converters |
| Filtering Capacitors |
Electrolytic: 7x Lelon (4-7,000h @ 105°C, RXW), 2x Teapo (3-6,000h @ 105°C, SY) Polymer: 1x Elite, 5x Lelon, 2x no info |
| Supervisor IC | IN1S429I - DCG |
| Fan Model | Champion CF1325H12D (135mm, 12V, 0.6A, Double Ball Bearing) |
| 5VSB Circuit | - |
| Rectifier | 1x PFC PFR30L45CT SBR (45V, 30A) |
| Standby PWM Controller | Power Intergrations TNY278PN |
The platform is modern. Typically lower efficiency units use older platforms, with the only modern touch being the DC-DC converters on the secondary side. In this case, though, GW used a half-bridge topology and an LLC resonant converter, a design that we meet in higher efficiency platforms. Moreover, a synchronous design regulates the 12V rail on the secondary side.
The significant compromises that had to be made to keep the cost low were the low-quality bulk and filtering caps and the fixed cables. We don't mind much about the latter, but we do mind the Lelon caps.
The transient/EMI filter has all require parts and it does an almost perfect job.
The single bridge rectifier can handle up to 15A at 100°C.
The APFC converter uses two FETs and a single boost diode. The bulk cap is rated at 450V and 105°C, but its capacity is low, and to make things even worse, it is by Lelon, which is not among the good capacitors brands.
The primary switching FETs are two STMicroelectronics installed in a half-bridge topology. An LLC resonant converter is also used for increased efficiency.
Four FETs regulate the 12V rail and a pair of DC-DC converters handle the minor rails.
The filtering caps are mostly by Lelon and Teapo. The Lelon caps have good specs. Nonetheless, we would prefer if all caps were by Teapo.
The standby PWM controller is a TNY278PN IC. The rectifier on the secondary side of this circuit is an SBR.
The main supervisor IC is an IN1S429I - DCG.
Soldering quality is good.
The cooling fan uses a double ball-bearing. We didn't expect to find a quality DBB fan in this PSU.
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