Best PSU for Core i7-12700K & RTX 4090
This build is an enthusiast-tier powerhouse, excelling in 4K gaming, professional content creation, and demanding tasks with ease, offering top-tier performance.
1000W
675W
68%
Enthusiast
🏆 Recommended Power Supplies
Hand-picked for your 1000W target — sorted by overall value.
CORSAIR RM1000x ATX 3.1 PCIe 5.1 Ready Fully Modular 1000W Power Supply – Low-Noise, Cybenetics Gold Efficiency, Native 12V-2×6 Connector – Black
Excellent reputation, ATX 3.1, PCIe 5.1, and 12V-2×6 ensure reliable, quiet power for high-end components.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$179.99
Rosewill VMG 1000W 80+ Gold, ATX 3.0 & 3.1 Compatible, Full Modular Low-Noise Power Supply, PCIe 5.1 12V-2×6 Connector, 100% Japanese Electrolytic Capacitor, 120mm FDB Silent Fan – 5 Year Warranty
ATX 3.0/3.1, PCIe 5.1, 12V-2×6, and Japanese capacitors provide stable, efficient power for this demanding system.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$89.99
msi MAG A1000GL PCIE5, Fully Modular Compact Gaming 1000W Power Supply, 80+ Gold, ATX 3.1 & PCIe 5.1 Ready, Native Dual-Color 12V-2×6 Cable, 10 Year Warranty
ATX 3.1, PCIe 5.1, and a native 12V-2×6 cable make it perfectly suited for the RTX 4090 and i7-12700K.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$134.99
Corsair RM1200x Shift Fully Modular ATX Power Supply – Side Interface – ATX 3.1 & PCIe 5.1 Compliant – Zero RPM Fan Mode – 105°C-Rated Capacitors – 80 Plus Gold Efficiency – Black
Want extra headroom for future GPU upgrades or overclocking? This 1200W unit gives you peace of mind.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$194.99
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📊 Quick Comparison
See the key differences at a glance.
| # | Model | Wattage | Efficiency | Modular | Price |
|---|---|---|---|---|---|
| 1 | CORSAIR RM1000x ATX 3.1 PCIe 5.1 Ready Fully Modular 1000W Power Supply – Low-Noise, Cybenetics Gold Efficiency, Native 12V-2×6 Connector – Black | 1000W | 80+ Gold | Full-Modular | $179.99 |
| 2 | Rosewill VMG 1000W 80+ Gold, ATX 3.0 & 3.1 Compatible, Full Modular Low-Noise Power Supply, PCIe 5.1 12V-2×6 Connector, 100% Japanese Electrolytic Capacitor, 120mm FDB Silent Fan – 5 Year Warranty | 1000W | 80+ Gold | Full-Modular | $89.99 |
| 3 | msi MAG A1000GL PCIE5, Fully Modular Compact Gaming 1000W Power Supply, 80+ Gold, ATX 3.1 & PCIe 5.1 Ready, Native Dual-Color 12V-2×6 Cable, 10 Year Warranty | 1000W | 80+ Gold | Full-Modular | $134.99 |
| ⬆️ | Corsair RM1200x Shift Fully Modular ATX Power Supply – Side Interface – ATX 3.1 & PCIe 5.1 Compliant – Zero RPM Fan Mode – 105°C-Rated Capacitors – 80 Plus Gold Efficiency – Black Upgrade | 1200W | 80+ Gold | Full-Modular | $194.99 |
🔌 Power Budget
Your system uses 68% of the recommended PSU output — well within the efficient operating range.
1000W (Recommended)
System draw: 675W
Headroom: 325W (30%)
💡 Why 1000W?
Power Calculation
CPU + GPU draw, plus ~100W for motherboard, RAM, fans, and storage.
30% Headroom
Extra capacity absorbs transient power spikes, keeps efficiency in the sweet spot, and leaves room for future upgrades.
80 Plus Efficiency
We only recommend certified PSUs. Higher ratings mean less wasted energy, lower heat, and quieter fans.
🌿 Power Efficiency Tips
Enable CPU power-saving features.
Optimize GPU power limits.
Ensure good case airflow.
🎯 What This Build Can Do
4K Gaming
Experience all games at max settings and high frame rates, even with ray tracing.
3D Rendering
Render complex scenes and animations quickly with the powerful CPU and GPU.
AI/ML Development
Train large machine learning models and perform data analysis with top-tier performance.
🔧 Installation Guide
Quick Checklist
- Mount the PSU with its fan aligned to your case airflow.
- Only connect cables you actually need (modular PSUs).
- Use dedicated PCIe power cables for NVIDIA GeForce RTX 4090 — no daisy-chaining.
- Boot-test with side panel open before final assembly.
⚠️ Special Note
Connect all necessary modular cables before mounting PSU for easier access.
🔗 Explore More Builds
See PSU recommendations for other CPU + GPU combinations.