Best PSU for Core i5-14400 & RTX 4090
Your system with Intel Core i5-14400 and NVIDIA GeForce RTX 4090 provides excellent performance for most demanding tasks. This high-end configuration offers smooth 4K gaming, efficient video rendering, and multitasking with resource-intensive applications.
850W
615W
72%
High-end
🏆 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
Excellent efficiency rating, ideal for extended use with this Intel Core i5-14400 and NVIDIA GeForce RTX 4090 configuration.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$118.99
Cooler Master MWE Gold 850 V2 Fully Modular Power Supply – 850W 80+ Gold Certified PSU, Dual EPS Connectors, Semi-Fanless Low Noise Design, Flat Black Cables, Reliable ATX Gaming PSU, 5-Year Warranty
Excellent efficiency rating, ideal for extended use with this Intel Core i5-14400 and NVIDIA GeForce RTX 4090 configuration.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$89.99
CORSAIR RM850x ATX 3.1 PCIe 5.1 Ready Fully Modular 850W Power Supply – Low-Noise, Cybenetics Gold Efficiency, Native 12V-2×6 Connector – Black
Excellent efficiency rating, ideal for extended use with this Intel Core i5-14400 and NVIDIA GeForce RTX 4090 configuration.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$129.99
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
Want extra headroom for future GPU upgrades or overclocking? This 1000W unit gives you peace of mind.
Efficiency80+ Gold
FormATX
CablesFull-Modular
Price$89.99
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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 | Cooler Master MWE Gold 850 V2 Fully Modular Power Supply – 850W 80+ Gold Certified PSU, Dual EPS Connectors, Semi-Fanless Low Noise Design, Flat Black Cables, Reliable ATX Gaming PSU, 5-Year Warranty | 850W | 80+ Gold | Full-Modular | $89.99 |
| 3 | CORSAIR RM850x ATX 3.1 PCIe 5.1 Ready Fully Modular 850W Power Supply – Low-Noise, Cybenetics Gold Efficiency, Native 12V-2×6 Connector – Black | 850W | 80+ Gold | Full-Modular | $129.99 |
| ⬆️ | 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 Upgrade | 1000W | 80+ Gold | Full-Modular | $89.99 |
🔌 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
Enable Windows/OS power saving features when not gaming to reduce power consumption and heat output.
Consider investing in a high-quality UPS to protect your high-end components from power surges and outages.
Monitor component temperatures and adjust fan curves for optimal balance between cooling performance and noise.
🎯 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
Your NVIDIA GeForce RTX 4090 requires the new 12VHPWR power connector. Ensure your PSU includes this connector or use the appropriate adapter, and make sure it's fully inserted to prevent connection issues.
🔗 Explore More Builds
See PSU recommendations for other CPU + GPU combinations.



