The FSP Mega GM 1200W stands out for a reason many buyers overlook: it is FSP’s own design, engineered and assembled under its own roof rather than a contracted platform wearing another company’s label. FSP has been a heavyweight in the power-supply business for three decades. Founded in Taiwan in April 1993 as a joint venture between Fortron/Source of the United States, Sparkle Power International, and Powertech Systems, the company grew into one of the largest power-supply manufacturers in the world. It served as one of Intel’s early seed partners during the formative years of the ATX standard and was listed on the Taiwan Stock Exchange in 2002. When most companies need a power supply, they call an OEM, and FSP is frequently the one that gets the call.
That background matters here because the Mega GM is a genuine in-house product. The series spans 850W, 1000W, and the 1200W flagship reviewed here, all built to the same ATX 3.1 and PCIe 5.1 specification. That means native 12V-2×6 delivery, support for the 200% transient power excursions that modern GPUs demand, and FSP’s proprietary MTLC (Micro Tolerance Load Control) regulation scheme. It is positioned as a Gold-class product, yet in testing it behaves like a unit a tier above.
Specifications and Design
The Mega GM 1200W carries a EUR 197 MSRP and a 10-year warranty. It accepts 100 to 240 VAC at 50 to 60 Hz and delivers a full 1200W on the +12V rail (100A). The +3.3V and +5V rails are each rated at 100W (20A), with 15W on +5Vsb and 3.6W on -12V, all rated at 50 °C.
The unit ships in a clean black box with a high-resolution render and certifications printed on the front: 80 PLUS Gold, Cybenetics Gold, the Cybenetics A++ acoustic award, plus the PCIe 5.1 and ATX 3.1 badges. Oddly, the unit’s actual certifications do not line up with those printed on the packaging.
Inside, the supply is protected in a molded cardboard housing with accessories boxed separately. The bundle is sensible rather than lavish: mounting screws, the AC power cable, cable ties, cable combs, an ATX jump-start tester, documentation, and a storage pouch for unused cables.
Cables, Connectors, and Dimensions
The cables are individually sleeved with FSP’s embossed weave and shipped in two tidy bundles secured with reusable straps, with gauges appropriate to the tier. The headline inclusion is the native 12V-2×6 lead, delivering a full 600W with no adapters, which is exactly what an RTX 50-series build needs. However, only one is provided, a limitation for a 1200W unit.
Connectivity includes a hardwired ATX 24-pin, two EPS 4+4-pin CPU connectors, one PCIe 5.1 (12V-2×6), three PCIe 8-pin (6+2), ten SATA, and six Molex connectors.
Measuring 150 x 150 x 86 mm, the Mega GM
Source
Image: tomshardware.com
