Best PSU for Core i5-14400F & RTX 4090
This build delivers exceptional 4K gaming and content creation performance. The i5-14400F might bottleneck the RTX 4090 in some CPU-intensive scenarios.
850W
615W
72%
Enthusiast
🏆 Recommended Power Supplies
Hand-picked for your 850W target — sorted by overall value.
MSI MAG A850GL PCIE5, Fully Modular Compact Gaming 850W Power Supply, 80+ Gold, ATX 3.1 & PCIe 5.1 Ready, Native Dual-Color 12V-2×6 Cable, 10 Year Warranty
This 850W ATX 3.1 PSU provides ample, stable power for the RTX 4090 and i5, with future-proofing.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$109.99
CORSAIR RM850e ATX 3.1 PCIe 5.1 Ready Fully Modular 850W Power Supply – 12V-2×6 Cable Included, Cybenetics Gold Efficiency, 105°C-Rated Capacitors, Modern Standby Mode – Black
Reliable 850W ATX 3.1 PSU with 12V-2×6 cable perfectly powers the RTX 4090 and i5, ensuring stability.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$102.29
Rosewill VMG 850W 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
Its 850W ATX 3.1 design and PCIe 5.1 readiness deliver robust power for the RTX 4090 and i5.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$74.96
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
Want extra headroom for future GPU upgrades or overclocking? This 1000W unit gives you peace of mind.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$134.99
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📊 Quick Comparison
See the key differences at a glance.
| # | Model | Wattage | Efficiency | Modular | Price |
|---|---|---|---|---|---|
| 1 | MSI MAG A850GL PCIE5, Fully Modular Compact Gaming 850W Power Supply, 80+ Gold, ATX 3.1 & PCIe 5.1 Ready, Native Dual-Color 12V-2×6 Cable, 10 Year Warranty | 850W | 80+ Gold | Full-Modular | $118.99 |
| 2 | CORSAIR RM850e ATX 3.1 PCIe 5.1 Ready Fully Modular 850W Power Supply – 12V-2×6 Cable Included, Cybenetics Gold Efficiency, 105°C-Rated Capacitors, Modern Standby Mode – Black | 850W | 80+ Gold | Full-Modular | $124.99 |
| 3 | Rosewill VMG 850W 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 | 850W | 80+ Gold | Full-Modular | $74.97 |
| ⬆️ | 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 Upgrade | 1000W | 80+ Gold | Full-Modular | $134.99 |
🔌 Power Budget
Your system uses 72% of the recommended PSU output — well within the efficient operating range.
850W (Recommended)
System draw: 615W
Headroom: 235W (30%)
💡 Why 850W?
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
Consider GPU undervolting for lower power consumption.
Utilize OS and driver power-saving features.
Enable V-sync or frame caps to reduce GPU load.
🎯 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 PSU and components.
🔗 Explore More Builds
See PSU recommendations for other CPU + GPU combinations.