Best PSU for Ryzen 9 3950X & RTX 4090
This build delivers exceptional 4K gaming performance with max settings and ray tracing. It's also highly capable for demanding creative and productivity workloads.
1000W
655W
66%
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
Trusted brand, 80+ Gold efficiency, and native 12V-2×6 connector provide reliable power for your RTX 4090.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$159.99
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 3.1, 80+ Gold, and 12V-2×6 connector ensure stable power delivery for this demanding RTX 4090 system.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$95.97
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 ready with 12V-2×6 cable, 80+ Gold, ideal for this powerful enthusiast build.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$134.99
MONTECH Century II – 1200W High-End ATX Gaming Power Supply – 80 Plus Gold & Cybenetics Platinum – Fully Modular – ATX 3.1 & PCIe 5.1 Ready with 12V-2×6 Cable – 10 Years Warranty
Want extra headroom for future GPU upgrades or overclocking? This 1200W unit gives you peace of mind.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$119.89
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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 |
| ⬆️ | MONTECH Century II – 1200W High-End ATX Gaming Power Supply – 80 Plus Gold & Cybenetics Platinum – Fully Modular – ATX 3.1 & PCIe 5.1 Ready with 12V-2×6 Cable – 10 Years Warranty Upgrade | 1200W | 80+ Gold | Full-Modular | $129.90 |
🔌 Power Budget
Your system uses 66% of the recommended PSU output — well within the efficient operating range.
1000W (Recommended)
System draw: 655W
Headroom: 345W (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
Undervolt GPU for better efficiency and lower heat.
Optimize CPU power settings via BIOS for balanced performance.
🎯 What This Build Can Do
Gaming
Suitable for modern games with good performance based on your system configuration.
Productivity
Great for office work, multitasking, and everyday computing tasks.
Content Creation
Can handle basic video editing and content creation workflows.
🔧 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
Ensure all modular cables are fully seated into both the PSU and components.
🔗 Explore More Builds
See PSU recommendations for other CPU + GPU combinations.