The RTX 5090 draws up to 575W on its own and runs on a single 12V-2x6 connector with a 600W ceiling, so a 1000W unit leaves little room once you add a flagship CPU and a few NVMe drives. That is the reason the 1200W to 1500W tier has become the default for no-compromise builds. These five units are the ones with a verifiable ATX 3.1 or PCIe 5.x design and a native 12V-2x6 cable, compared on efficiency, connectors, noise, and warranty from published reviews and manufacturer specs.
| Spec | Corsair HX1200i (2025) 9.3/10 | MSI MPG A1250GS PCIE5 8.9/10 | Corsair HX1500i (2025) 9.1/10 | Seasonic PRIME TX-1300 8.8/10 | Corsair HX1200i Shift Unavailable 8.4/10 |
|---|---|---|---|---|---|
| wattage | 1200W | 1250W | 1500W | 1300W | 1200W |
| efficiency | Cybenetics Platinum (89.65% at 115V) | 80 Plus Gold | 80 Plus Platinum | 80 Plus Titanium | Cybenetics Platinum |
| standard | ATX 3.1 / PCIe 5.1 | ATX 3.1 / PCIe 5.1 | ATX 3.1 / PCIe 5.1 | ATX 3.0 / PCIe 5.0 | ATX 3.1 / PCIe 5.1 |
| connector | 1x 12V-2x6 (600W) | 2x 12V-2x6 (600W each) | Native 12V-2x6, 3x EPS12V | Native 12VHPWR | Native 12V-2x6, side-mounted ports |
| fan | 140mm FDB, semi-passive | Low-noise fan, semi-digital design | 140mm FDB, Zero RPM mode | Digital fan control, A++ noise | 140mm FDB, Zero RPM mode |
| warranty | 10 years | 10 years | 10 years | See manufacturer | 10 years |
| Rating | 9.3/10 | 8.9/10 | 9.1/10 | 8.8/10 | 8.4/10 |
Prices change daily — tap Check Price for the current Amazon price.
Prices change daily — tap Check Price for the current Amazon price.
Quick Picks
- Best overall: the Corsair HX1200i (2025). Platinum efficiency, a quiet 140mm fan, and a 10-year warranty in a 200mm-deep body.
- Best for dual 12V-2x6: the MSI MPG A1250GS PCIE5. It is the only unit here with two native 12V-2x6 cables.
- Best for maximum headroom: the Corsair HX1500i (2025). 1500W covers workstation CPUs plus an RTX 5090.
- Best efficiency and noise: the Seasonic PRIME TX-1300. Titanium-rated with an A++ noise score.
Buying Guide
Wattage. Add the GPU’s board power to the CPU’s maximum power draw, then add roughly 100W for the rest of the system. An RTX 5090 at 575W plus a 250W CPU lands near 925W of peak draw, which is why 1000W is the stated minimum and 1200W is the comfortable choice. For how CPU power ratings translate to real draw, see our TDP explained guide.
12V-2x6 cables. A single 12V-2x6 cable is rated for up to 600W. Native cables avoid adapter bends that stress the connector, so favor units that ship the cable instead of relying on a 4x 8-pin adapter. If you plan to run two high-power GPUs, count the 12V-2x6 cables, not just total wattage.
ATX 3.1 versus ATX 3.0. ATX 3.1 is the newer revision and the one the Corsair and MSI units here are built to. The Seasonic PRIME TX-1300 follows ATX 3.0 and PCIe 5.0, which still supports 12VHPWR GPUs but is a generation behind on the spec.
Efficiency tier. Gold, Platinum, and Titanium differ by a few percentage points at typical load. Over a year of gaming that is a small difference on a power bill, so pay for a higher tier only if you also want the quieter fan behavior that tends to come with it.
Physical fit. The HX1200i measures 150 x 85 x 200mm. Check that your case has PSU-shroud clearance for the cables, especially in compact cases. Our best modular power supplies roundup covers cable length considerations in more depth.
Detailed Reviews
1. Corsair HX1200i (2025)
The Corsair HX1200i is the unit to buy for a single-GPU high-end build. Hardware Busters’ published measurements show Cybenetics Platinum efficiency of 89.65% at 115V and 91.47% at 230V, with an A+ noise rating of 15-20 dBA from the 140mm fluid dynamic bearing fan. It supplies a 100A single 12V rail, so the full 1200W is available to the GPU.
Connectors are two EPS, five PCIe 6+2 pin, one 12+2 pin 12V-2x6 (600W), eight SATA, and six Molex, with 610-650mm cables. The 10-year warranty matches the top tier of this roundup. It pairs well with the RTX 5090, as covered in our RTX 5090 review.
2. MSI MPG A1250GS PCIE5
The MSI MPG A1250GS is the dual-GPU answer. It provides two native 12V-2x6 cables, each rated for 600W, along with ATX 3.1 and PCIe 5.1 support, server-grade capacitors, and a semi-digital design. 80 Plus Gold efficiency is a tier below the Corsair HX units, so it will draw slightly more from the wall at equal load.
For a single RTX 5090 build, the extra 12V-2x6 cable is optional insurance. For a workstation that pairs a 5090 with a second accelerator, it is the reason to pick this unit over the HX1200i.
3. Corsair HX1500i (2025)
The Corsair HX1500i raises the ceiling to 1500W with the same HXi platform: Platinum efficiency, a 140mm FDB fan with Zero RPM mode, native 12V-2x6, and three EPS12V connectors. It suits builds with high-core-count CPUs that need dual CPU power cables alongside an RTX 5090.
Most gaming PCs peak under 1000W, so the extra 300W over the HX1200i is only worth it if you plan a heavy overclock or multi-accelerator workload.
4. Seasonic PRIME TX-1300
The Seasonic PRIME TX-1300 is an 80 Plus Titanium unit with fully modular cables, 105°C Japanese capacitors, and digital fan control. Published noise data shows a Cybenetics A++ rating with an average of 11.44 dBA, the quietest of this group.
The catch is the standard: it is built to ATX 3.0 and PCIe 5.0, not ATX 3.1, and it carries a Titanium premium. If you value silence and efficiency above spec recency, it is the premium pick. Our Corsair vs Seasonic comparison goes deeper on how the two brands compare.
5. Corsair HX1200i Shift
The Corsair HX1200i Shift moves every modular port to the side of the unit and adds an integrated iCUE LINK System Hub that controls up to 24 iCUE LINK devices. Power delivery matches the standard HX1200i: Cybenetics Platinum, A++ noise rating, 140mm FDB fan, native 12V-2x6, ATX 3.1.
Hardware Busters notes that higher-performing 1200W units exist for less money, and that the hub is the Shift’s main differentiator. Buy it only if your case and fans are already iCUE LINK.
Corsair HX1200i Shift
FAQ
Do I need a 1200W power supply for an RTX 5090?
The RTX 5090 draws up to 575W, and the manufacturer-recommended minimum is 1000W. A 1200W unit leaves headroom for transient spikes and a high-power CPU. If you want to compare against a smaller unit, see our 1000W power supply roundup.
Is a 1500W power supply overkill?
For a single-GPU gaming build, yes. The HX1500i makes sense for workstation CPUs with dual EPS requirements or builds with more than one high-power accelerator.
Does a second 12V-2x6 cable matter?
Only for multi-GPU systems. A single 12V-2x6 cable carries up to 600W, which covers one RTX 5090. The MSI A1250GS is the unit here that supplies two.
Should I buy ATX 3.1 or ATX 3.0?
Pick ATX 3.1 when available. ATX 3.0 units still power 12VHPWR GPUs, but ATX 3.1 is the current revision and the one newer Corsair and MSI units follow.
The Bottom Line
For most RTX 5090 builds, buy the Corsair HX1200i (2025): Platinum efficiency, a quiet fan, and a 10-year warranty. Choose the MSI MPG A1250GS if you need two 12V-2x6 cables, the Corsair HX1500i if you need 1500W, and the Seasonic PRIME TX-1300 if silence and efficiency outrank having the newest spec.