Best PSU for Core i9-14900KS & RTX 4090
This enthusiast build excels at 4K gaming, professional content creation, and demanding workstation tasks, offering top-tier performance across all applications.
1000W
700W
70%
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 choice, known for reliability, low noise, and ATX 3.1/PCIe 5.1 readiness, perfect for this high-end system.
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
Solid option with ATX 3.1/PCIe 5.1, Japanese capacitors, and FDB fan, ensuring stable and quiet power delivery.
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
Strong contender with ATX 3.1/PCIe 5.1, compact design, and a long warranty, ideal for powerful gaming rigs.
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 70% of the recommended PSU output — well within the efficient operating range.
1000W (Recommended)
System draw: 700W
Headroom: 300W (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 in BIOS.
Utilize GPU frame rate limits for less demanding games.
Ensure proper case airflow for optimal cooling efficiency.
🎯 What This Build Can Do
4K Gaming
Max settings, high refresh rate gaming on the latest AAA titles.
Video Editing
Fast rendering and smooth editing of 8K video and complex visual effects.
AI Development
Training large language models and complex machine learning algorithms efficiently.
🔧 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 securely connected to both PSU and components before powering on.
🔗 Explore More Builds
See PSU recommendations for other CPU + GPU combinations.