Best PSU for AMD Ryzen 9 7900 and NVIDIA GeForce RTX 5070
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NVIDIA GeForce RTX 5070
Configuration Analysis
System Performance Assessment
This system is capable of excellent performance in modern games at high resolutions (1440p and even 4K) with high refresh rates. The Ryzen 9 7900 and RTX 5070 are a powerful combination for demanding applications like video editing, streaming, and content creation. Expect smooth frame rates and responsive performance across a wide range of tasks.
Recommended Power Supplies

MSI MAG A550BN Gaming Power Supply – 80 Plus Bronze Certified 550W – Compact Size – ATX PSU

CORSAIR CX550 80 Plus Bronze Non Modular Low-Noise ATX 550 Watt Power Supply – NA – Black
The CX550's wattage is sufficient for your 7900/RTX 5070, and its efficiency will keep power draw reasonable. A solid, reliable choice.

Thermaltake Smart 500W 80+ White Certified PSU, Continuous Power with 120mm Ultra Quiet Cooling Fan, ATX 12V V2.3/EPS 12V Active PFC Power Supply PS-SPD-0500NPCWUS-W
The Thermaltake 500W is a solid, budget-friendly choice, providing stable power for your 7900 and RTX 5070 at reasonable power draw.
Comparison Table
Model | Wattage | Efficiency | Form Factor | Modularity | Price | Best For |
---|---|---|---|---|---|---|
MSI MAG A550BN Gaming Power Supply – 80 Plus Bronze Certified 550W – Compact Size – ATX PSU | 550W | 80+ Gold | ATX | Non-Modular | $59.99 | Overall Value |
CORSAIR CX550 80 Plus Bronze Non Modular Low-Noise ATX 550 Watt Power Supply – NA – Black | 550W | 80+ Gold | ATX | Non-Modular | $59.99 | Energy Efficiency |
Thermaltake Smart 500W 80+ White Certified PSU, Continuous Power with 120mm Ultra Quiet Cooling Fan, ATX 12V V2.3/EPS 12V Active PFC Power Supply PS-SPD-0500NPCWUS-W | 500W | 80+ White | ATX | Non-Modular | $40.99 | Budget Builds |
Why This Wattage?
Power Calculation
The recommended PSU wattage is calculated based on the total power draw of your CPU (AMD Ryzen 9 7900) and GPU (NVIDIA GeForce RTX 5070), plus approximately 100W for other components like motherboard, memory, and storage devices.
Extra Headroom
We add an additional 30% headroom to ensure optimal efficiency, handle power spikes, and allow for future upgrades. This ensures your system runs stable and your PSU operates in its optimal efficiency range.
Efficiency Standards
We recommend power supplies with 80 Plus certification, which represents higher energy efficiency and more reliable performance. Power supplies are most efficient at 50-60% load, so having adequate headroom is important.
Power Efficiency Tips
Enable AMD Eco Mode in BIOS to limit the CPU's TDP, reducing power consumption without significant performance impact.
Optimize NVIDIA Control Panel settings for your games, prioritizing performance or quality based on your preference for visual fidelity vs. power usage.
Ensure adequate case airflow to prevent components from overheating, which can lead to increased power consumption.
Special Installation Note
Given the RTX 5070's power demands, prioritize connecting it to the PSU using *two separate* PCIe power cables, rather than daisy-chaining one cable if possible, to ensure stable power delivery.
Usage Scenarios
AAA Gaming
Plays modern AAA games at high settings and resolutions (1440p/4K) with smooth frame rates and ray tracing enabled.
Content Creation
Handles video editing, graphic design, and 3D rendering tasks efficiently, leveraging both CPU and GPU power.
AI Development
Capable of running machine learning models and AI development tools, thanks to the powerful CPU and NVIDIA GPU's CUDA cores.
Installation Tips
Position Properly
Most cases have a dedicated PSU bay at the bottom. Ensure the PSU fan is facing down if your case has bottom ventilation, allowing it to draw cool air from outside.
Cable Management
With modular PSUs, connect only the cables you need. Route cables behind the motherboard tray when possible for better airflow and cleaner appearance.
Proper Connections
Ensure all power connectors are fully seated and locked. The NVIDIA GeForce RTX 5070 will require dedicated PCIe power connectors from the PSU.
Test Before Completing
Before fully closing your case, connect the essential components and test that your system boots correctly with the new power supply.
The MSI MAG A550BN's reliable 550W and 80+ Bronze rating are perfect for your Ryzen 9 and RTX 5070 setup without breaking the bank.