Corsair CX550F RGB Power Supply Review

The CX550F is one of the few Corsair PSUs with RGB lighting.

Corsair CX550F RGB
(Image: © Tom's Hardware)

Tom's Hardware Verdict

The Corsair CX550F offers good performance and high efficiency. The cherry on top for some of you will be the white color option and the RGB lighting.

Pros

  • +

    Full power at 47 degrees Celsius

  • +

    Good transient response at 12V

  • +

    Efficient

  • +

    Modern platform

  • +

    Rifle bearing fan

  • +

    Low leakage current

  • +

    Low conducted EMI

  • +

    Compatible with the Alternative Low Power Modes

  • +

    Fully modular

  • +

    Highly-customizable RGB lighting

  • +

    Comes in two colors

  • +

    5-year warranty

Cons

  • -

    Not so affordable

  • -

    Loose load regulation

  • -

    Lower than 17ms hold-up time

  • -

    Not fond of the Teapo SC caps that it uses

  • -

    Short distance between the peripheral connectors

Why you can trust Tom's Hardware Our expert reviewers spend hours testing and comparing products and services so you can choose the best for you. Find out more about how we test.

The CX550F is among the best mid-level PSUs featuring RGB lighting. Corsair teamed with HEC for its CX-F line, and it used a modern platform including a quality fan with advanced RGB lighting, meaning that the production costs increased; hence, the CX550F costs more than the category's average. Nonetheless, besides the eye-candy features, the unit also offers good performance and is not noisy under normal operating conditions. 

If you don't care much about the RGB lighting, which is the main reason to spend more and buy the CX550F, you can also look at the Corsair CX550M and the XPG Pylon 550. Both use less advanced platforms than the CX550F yet still offer higher overall performance. If we had an RGB category in our best PSUs article for mid-level units, the CX550F could be included. 

The Corsair CX550F is the lowest capacity member of the corresponding line, which has three members. They all feature RGB lighting and are based on a modern HEC platform. Moreover, they come in two colors, black and white, and all their cables are modular. The CX550F is rated Bronze in the 80 PLUS standard and Gold by Cybenetics. It also has a noise rating of Cybenetics-Standard++ (30-35 dB[A] average noise output). Usually, this unit goes for $90, so it isn't exactly affordable. However, during the review, Corsair offered it at a lower price of $65 and you could probably find it for less with a Corsair discount code from time to time too. 

Corsair sent us a white unit that looks great with the same color modular cables and the RGB lighting effects of the fan. The RGB lighting can be controlled through the optional Corsair iCUE RGB lighting controller or a compatible mainboard through the included 5V ARGB adapter. If you don't want to buy the Corsair controller and your mainboard doesn't support RGB control/sync, you can customize the PSU's lighting via a push-button at the front. 

To cycle through lighting modes, you must press and hold the button mentioned above for about three seconds. If the current mode isn't rainbow, you press the button shortly to cycle through colors. You should also remember that the push-button won't work if the PSU is in software control mode, connected to the Corsair controller or the mainboard. 

The available lighting modes are: rainbow wave, rainbow, rainbow breathe, rainbow blink, sequential, solid, single blink, and pulse. You also have the option to disable the fan's lighting. 

Specifications: Corsair CX550F RGB

Swipe to scroll horizontally

Manufacturer (OEM)

HEC

Max. DC Output

550W

Efficiency

80 PLUS Bronze, Cybenetics Gold (87-89%)
NoiseCybenetics-Standard++ (30-35 dB[A])

Modular

✓ (Fully)

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

120mm Rifle Bearing Fan (NR120L)

Semi-Passive Operation

Dimensions (W x H x D)

150 x 85 x 140mm

Weight

1.34 kg (2.95 lb)

Form Factor

ATX12V v2.4, EPS 2.92

Warranty

5 years

Power Specifications: Corsair CX550F RGB

Swipe to scroll horizontally
Rail 3.3V5V12V5VSB-12V
Max. PowerAmps202045.830.3
 Watts120549.6153.6
Total Max. Power (W) 550    

Cables & Connectors of Corsair CX550F RGB

Swipe to scroll horizontally
Modular CablesCable CountConnector Count (Total)GaugeIn Cable Capacitors
ATX connector 20+4 pin (610mm)1118-20AWGNo
4+4 pin EPS12V (650mm)1118AWGNo
6+2 pin PCIe (600mm+150mm)1216-18AWGNo
SATA (450mm+115mm+115mm+115mm)1418AWGNo
SATA (500mm+100mm+100mm)1318AWGNo
4 pin Molex (450mm+100mm+100mm+100mm)1418AWGNo
iCUE RGB cable (500mm)1128AWGNo
Motherboard ARGB cable (300mm)1128AWGNo
AC Power Cord (1380mm) - C13 coupler1118AWG-

The PSU's low capacity doesn't allow for more than one EPS and two PCIe connectors, with the last installed on the same cable. However, the number of peripheral connectors is adequate. 

All cables are long enough, but as usual, we would like to see longer distances between the peripheral connectors. However, the lack of in-cable caps is good news for most users It is also nice to see thicker 16AWG gauges up to the first PCIe connector for lower voltage drops since the same gauges have to handle a pair of these connectors. 

Component Analysis of Corsair CX550F RGB

We strongly encourage you to 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.

Swipe to scroll horizontally
General Data-
Manufacturer (OEM)HEC
PCB TypeSingle Sided
Primary Side-
Transient Filter4x Y caps, 2x X caps, 1x CM chokes, 1x DM chokes, 1x MOV, 1x Discharge IC (CAP200DG)
Inrush ProtectionNTC Thermistor SCK-037
Bridge Rectifier(s) 1x GBU10K (800V, 10A @ 100°C)
APFC MOSFETs 2x Infineon IPA60R280P7S (650V, 8A @ 100°C, 0.28Ohm)
APFC Boost Diode 1x Cree C3D04060A (600V, 4A @ 160°C)
Hold-up Cap(s) 1x Hitachi (400V, 330uF, 2,000h @ 105°C, HU)
Main Switchers 2x Champion GPT18N50DG (500V, 18A , 0.27Ohm)

 APFC Controller

Champion CM6500UNX & Champion CM03X

IC Driver MPS MP6924A 
Resonant ControllerMPS HR1001C
Topology Primary side: APFC, Half-Bridge & LLC converter
Secondary side: Synchronous Rectification & DC-DC converters
Secondary Side-
+12V MOSFETs4x Nexperia PSMN8R3-40YS (40V, 50A @ 100°C, 16mOhm @ 175°C)
5V & 3.3VDC-DC Converters: 8x Potens Semiconductor PDD3906 (30V, 51A @ 100°C, 6mOhm) 
PWM Controllers: ANPEC APW7073
Filtering CapacitorsElectrolytic: 12x Teapo (1-3,000h @ 105°C, SC) , 2x Nippon Chemi-Con (1-5,000h @ 105°C, KZE) Polymer: 16x Teapo
Supervisor ICWeltrend WT7527 (OCP, OVP, UVP, SCP, PG)
Fan ModelCorsair NR120L (120mm, 12V, 0.22A, RGB, Rifle Bearing Fan)
5VSB Circuit-
Rectifier 1x PS1060L SBR (60V, 10A)
Standby PWM ControllerPower Integrations TNY290PG
-12V-
Rectifier 1x KEC KIA7912PI (-12V, 1A)

Corsair helped HEC build this platform, which is advanced for a merely Bronze unit in the 80 PLUS scheme. The CX550F manages to be a little above the lowest Gold efficiency threshold in the Cybenetics scale, earning the corresponding efficiency certification. Instead of the typical double-forward topology we usually find in this category, HEC used a half-bridge topology and an LLC resonant converter for increased efficiency. Moreover, we see a synchronous design and a pair of DC-DC converters for the minor rails on the secondary side. 

The EMI filtering stage includes all necessary parts, so we expect low EMI emissions. There is also a discharge IC to restrict energy losses on the bleeding resistors. Moreover, there is a MOV for voltage surges and an NTC thermistor for lower inrush currents. The latter is not supported by a bypass relay, which is a bummer. 

The single bridge rectifier can handle up to 10 Amperes. 

The APFC converter uses two Infineon FETs and a single boost diode provided by the CREE. The bulk cap is by Hitachi, which sold its capacitor business to a Chinese brand. 

The APFC controller is a Champion CM6500 IC. Another Champion IC, the CM03X, is used to restrict vampire power by cutting off the APFC converter during standby. 

The main FETs are arranged in a half-bridge topology, while an LLC resonant converter boosts efficiency. It is controlled by an MPS HR1001C (opens in new tab) IC. 

The FETs that regulate the +12V rail are on the solder side of the main PCB. Four Nexperia FETs are used in total. The minor rails are generated through eight FETs and use an Anpec PWM controller. 

The electrolytic filtering caps on the secondary side are mostly provided by Teapo, and belong to the SC line. A large number of polymer caps are also used for ripple filtering purposes. 

The 5VSB circuit uses a single SBR on its secondary side. The PWM controller is a Power Integrations TNY290PG IC. 

Several polymer caps are installed on the modular board. 

Corsair CX550F

(Image credit: Tom's Hardware)

The supervisor IC is a Weltrend WT7527, supporting all essential protection features but OTP (Over Temperature Protection).

Soldering quality is good

The cooling fan uses a rifle bearing, so it will last a long time. Its RGB lighting is also of good quality. 

MORE: Best Power Supplies

MORE: How We Test Power Supplies

MORE: All Power Supply Content

Aris Mpitziopoulos
Contributing Editor

Aris Mpitziopoulos is a Contributing Editor at Tom's Hardware US, covering PSUs.

  • Panzerbjorne39
    Curious why a rifle bearing fan is listed here under a Pro. Isn’t that the cheaper and louder of the common fan bearings?
    Reply