The Cooler Master GX III 1250W is a high capacity PSU, compatible with the ATX v3.0 spec, meaning that you will find a 12VHPWR header on its modular panel. If it used 2x 8pin sockets instead, it could be ATX v3.1 without any other changes!
The Cooler Master GX III 1250W is included in my best ATX v3.x & PCIe 5.x PSU picks article.
Cooler Master works with several OEMs, including Lite-On, which is mostly known for its power adapters. Lite-On wants to move into the desktop PSU market (I don’t know why; several other big OEMs, including Delta, have tried to do so lately). Hence, its cooperation with Cooler Master is an excellent opportunity to get familiar with this market segment. The GX III 1250 is an ATX v3.0 and PCIe 5.0 certified unit, meaning it has a 12VHPWR header on its modular panel. Replacing it with a 12V-2×6 can meet the newest ATX v3.1 and PCIe 5.1 specifications, and I suspect that CM will soon upgrade this platform. This could be a silent upgrade, but most likely, it will be advertised with the corresponding logos on the product’s packaging. CM could also use the Cybenetics corresponding ATX v3.x “pass” badges provided to PSUs that meet all corresponding requirements.
The GX III 1250 has Gold efficiency in the Cybenetics scheme and a Cybenetics Standard++ (30-35 dB[A]) noise rating. The unit’s dimensions are compact, with a depth of 160mm, which is low for its 1250W max power. Moreover, CM used a Hong Hua fan, which seems to be the standard for today’s high-end PSUs. Lastly, the provided warranty is ten years long, meeting the competition’s terms.
- Manufacturer (OEM): Lite-On
- Max Power: 1250W
- Cybenetics Efficiency: [115V] Cybenetics Gold (87-89%)
- 80 Plus Efficiency: Gold
- Noise [115V]: Cybenetics Standard++ (30-35 dB[A])
- Compliance: ATX v3.0, EPS 2.92
- Operating Temperature (Continuous Full Load): 0 – 50 °C
- Alternative Low Power Mode support: Yes
- Power 12V combined: 1250W
- Number of 12V rails: 1
- Power 5V + 3.3v: 120W
- Power 5VSB: 15W
- Cooling: 135mm Fluid Dynamic Bearing Fan (HA13525H12F-Z)
- Semi-Passive Operation: ✓
- Modular Design: Yes (Fully)
- High Power Connectors: 2x EPS (2x cables), 3x PCIe 6+2 pin (3x cables), 1x PCIe 12+4 pin (600W)
- Peripheral Connectors: 12x SATA (3x cables), 4x 4-pin Molex (single cable)
- ATX Cable Length: 610mm
- EPS Cable Length: 600mm
- 6+2 pin PCIe Cable Length: 550mm
- 12+4 pin PCIe Cable Length: 650mm
- Distance between SATA / 4-pin Molex: 120mm
- In-cable capacitors: No
- Dimensions (W x H x D): 150 mm x 85 mm x 160mm
- Weight: 1.87 kg (4.12 lb)
- Warranty: ten years
- Street price (excluding VAT): $242
Power Specifications
| Rail | 3.3V | 5V | 12V | 5VSB | -12V | |
| Max. Power | Amps | 20 | 20 | 104.1 | 3 | 0.3 |
| Watts | 120 | 1249.2 | 15 | 3.6 | ||
| Total Max. Power (W) | 1250 | |||||
