Asus ROG Thor 1200W PSU Review: Asus Brings a Screen to the PSU Party

The ROG Thor 1200W achieves good performance in all areas and besides that, it is the quietest PSU in its wattage category achieving an impressive LAMBDA-A+ (15-20 dB[A] overall noise output) certification in the Cybenetics scale.

Asus teamed up with Seasonic for its latest high-end PSU line, and the results are very promising. The embedded OLED screen provides real-time power draw data and there is also addressable RGB lighting and Aura Sync compatibility, for those who want their power supply to look fancy. The price that Asus asks for it is high but fair, given the product's features. The main competitors of Asus' high-end offering are the similar capacity Seasonic Prime Platinum and the Corsair AX1200i. The latter, despite its age, is still a worthy adversary.

Asus makes several different types of components, so it makes sense for the company to enter the PSU market. But since the cost of developing a PSU from the scratch is huge, the company decided to team up with Seasonic and modify its Prime and Focus platforms, for the Rog Thor 1200W and 850W models respectively. Here we'll be taking a good look at the strongest Thor unit, which looks to be a heavily modified Seasonic Prime Platinum model. We'll investigate not just the internals, but take a close look at the external design as well. The Thor units have nice aesthetics, addressable RGB lighting, and an impressive OLED screen. The latter really sets this unit apart from the competition, although it only provides power draw data and not DC wattage information.

Specifications

Manufacturer (OEM)Seasonic
Max. DC Output1200W
Efficiency80 PLUS Platinum, ETA-A (88-91%)
NoiseLAMBDA-A+ (15-20 dB[A])
Modular✓ (Fully)
Intel C6/C7 Power State Support
Operating Temperature (Continuous Full Load)0 - 50°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
Cooling135mm Double Ball Bearing Fan (PLA13525B12M)
Semi-Passive Operation✓ (selectable)
Dimensions (W x H x D) 152 x 88 x 192mm
Weight2.37 kg (5.22 lb)
Form FactorATX12V v2.4, EPS 2.92
Warranty10 Years

Power Specifications

Rail3.3V5V12V5VSB-12V
Max. PowerAmps252510030.3
Watts1251200153.6
Total Max. Power (W)1200

Cables & Connectors

Modular Cables
DescriptionCable CountConnector Count (Total)GaugeIn Cable Capacitors
ATX connector 20+4 pin (610mm)1118-20AWGNo
4+4 pin EPS12V (650mm)2218AWGNo
6+2 pin PCIe (680mm)4418AWGNo
6+2 pin PCIe (680mm+70mm) 2418AWGYes
SATA (350mm+150mm+150mm+150mm)1418AWGNo
SATA (400mm+115mm+115mm+115mm)2818AWGNo
4-pin Molex to 2x SATA (150mm)1218AWGNo
4-pin Molex (350mm+120mm)1218AWGNo
4-pin Molex (450mm+120mm+120mm)1318AWGNo
FDD Adapter (+105mm)1122AWGNo
RGB Cable (800mm)1122AWGNo
RGB Sync Cable (800mm)1124AWGNo
AC Power Cord Type (1380mm)1118AWG-

The amount of provided cables and connectors here is impressive! Besides two EPS connectors, the unit also has eight PCIe cables with four them being installed on dedicated cables. Moreover, you will find twelve SATA and a pair of SATA 3.3-compatible connectors, supporting the Power Disable function. In the latter the 3.3V rail is absent from the SATA connectors, since it doesn't exist on the four-pin Molex connector responsible for feeding them with power.

The only problems that we find here are the short distances between the peripheral connectors and the use of 18AWG gauges in the ATX, EPS and PCIe cables. Normally, in large-capacity units like this one, 16AWG gauges should be used for lower voltage drops under high loads.

Component Analysis

General Data
Manufacturer (OEM)Seasonic
Platform ModelPrime Ultra Platinum
Primary Side
Transient Filter6x Y caps, 4x X caps, 2x CM chokes, 1x MOV
Inrush ProtectionNTC Thermistor & Relay
Bridge Rectifier(s)2x Vishay LVB2560 (600V, 25A @ 105°C)
APFC MOSFETS2x Infineon IPP60R099CP (650V, 19A @ 100°C, 0.099 Ohm)
APFC Boost Diode1x STMicroelectronics STPSC10H065D (650V, 10A @ 135°C)
Hold-up Cap(s)Hitachi (400V, 1x 820uF & 1x 470uF, 2000h @ 105°C, HU)
Main Switchers4x Infineon IPP50R199CP (550V, 11A @ 100°C, 0.199 Ohm)
Drivers For Main Switchers2x Silicon Labs Si8230BD
APFC ControllerON Semiconductor NPC1654
Current Sensor ICAllegro ACS725T
Switching ControllerChampion CM6901
TopologyPrimary side: Full-Bridge & LLC Resonant Converter
Secondary side: Synchronous Rectification & DC-DC converters
Secondary Side
+12V MOSFETS8x Vishay SiR638DP (40V, 100A @ 70°C, 0.88mOhm)
5V & 3.3VDC-DC Converters: 6x Infineon BSC0906NS
PWM Controller: APW7159
Filtering CapacitorsElectrolytics: Chemi-Con (105°C, W), Chemi-Con (4,000-10,000h @ 105°C, KY, KYB), Rubycon (6,000-10,000h @ 105°C, ZLH), 1x Rubycon (5VSB circuit, 105°C, YXD)
Polymers: FPCAP, Nippon Chemi-Con
Micro ControllerMicrochip ATmega8A
Flash MemoryMicrochip SST26VF016B
Supervisor ICWeltrend WT7527V (OVP, UVP, OCP, SCP, PG ) & AS393M
Fan ModelPower Logic PLA13525B12M (135mm, 12V, 0.40A, 2000 RPM, 111.1 CFM, 41.6 dB[A], Double Ball Bearing)
5VSB Circuit
Buck ConverterLeadtrend LD7750R
Rectifiers STMicroelectronics STU6N65K3 (650V, 3A @ 100°C, 1.3Ohm)
-12V Circuit
Buck ConverterLite-On LSP5523 (3A max output current )

Asus asked Seasonic for a number of modifications on the Prime Platinum platform, with the most important being the installation of a micro-controller, which aside from providing a digital interface is also responsible for the circuit that provides the power draw data. All heatsinks have been replaced with larger ones for this Asus model, in order to allow for decreased airflow leading to reduced acoustic noise.

The majority of PSU manufacturers try to reduce the size of the heatsinks in order to save money, something that demands more-aggressive fan speed profiles. But Asus chose a different route, making the Rog Thor 1200W one of the quietest units in this category.

All components used in this platform are of high quality, and what particularly makes a good impression is the ball-bearing fan, which is much more heat-tolerant compared to FDB fans. FDB fans generally feature a quieter operation, and this is what makes this unit unique. Even with a noisier DBB fan, the Thor manages to achieve very low overall noise output.