Is a 450W PSU Sufficient for an AMD Radeon RX 6600?

When it comes to powering your build, the choice of a Power Supply Unit (PSU) plays a crucial role. Specifically, with an AMD Radeon RX 6600 graphics card paired with an Intel i5 or AMD Ryzen 5/7 CPU, a 450W PSU can be sufficient, given the right conditions. However, it is important to understand the various factors involved when making this decision.

General Guidelines for Sufficient Power Supply

A 450W PSU is generally considered sufficient for the AMD Radeon RX 6600 graphics card, provided the rest of your system isn't too power-hungry. The average power consumption of the RX 6600 is around 132W, with a recommended PSU ranging from 450W to 500W, depending on the overall system configuration.

Key Considerations

1. Overall System Power Consumption: Ensure that the combined power draw of your CPU, RAM, storage devices, and other components does not exceed the PSU's capacity when considering the RX 6600.

2. Quality of the PSU: A high-quality PSU with good efficiency ratings (80 Plus Bronze or better) is essential. Cheaper or lower-quality PSUs may not deliver their rated wattage reliably.

3. Headroom: It's a good practice to have some headroom, about 20-30% more than your system's maximum power draw, to ensure stability and the longevity of the PSU.

Real-World Experiences and Expert Opinions

However, some users have reported issues with using a 450W PSU with an RX 6600, leading to crashes in games and modern applications, especially on demanding systems. According to a user who owns a RG6600 Gigabyte Eagle with a 450W power supply, current spikes can cause hard crashes or the system to shut off and then reboot.

Experts recommend getting a higher PSU, ranging from 550W to 650W, to be on the safe side. A video from Linus Tech Tips demonstrates overcurrent causes by the GPU, showing the risk involved with using lower-wattage PSUs in demanding configurations.

Deep Dive into PSU Configuration

The specific PSU model and your CPU play crucial roles. Your SSD and RAM together will not use a significant amount of power. 16GB of RAM draws about 10W, while an NVMe SSD typically uses only about 5W. Even a low-end CPU would use about 50W, and the most power-hungry CPU for your motherboard (AMD Ryzen 9 595) can use up to 142W.

The RX 6600's thermal design power (TDP) is 132W, so a typical RX 6600 would use around that much power. Factory-overclocked (OC) models might use slightly more, up to about 150W, and require an 8-pin PCIe power connector.

Modern PSUs deliver the overwhelming majority of their power as 12V, which is the voltage used to supply power to modern CPUs and GPUs after conversion to a lower voltage by a VRM or "Voltage Regulator Module." However, some older PSUs deliver most of their power on 3.3V or 5V rails, which used to be used for CPUs. If your 450W PSU only delivers about 250W or less on its 12V rail, it might not be sufficient to power both your CPU and an RX 6600 simultaneously.

PSUs should have a label showing how much power they provide at different voltages. As long as your PSU provides more than 350W at 12V, it should be sufficient for your needs. One that delivers almost all of its 450W at 12V would be ideal for efficiency. Your SSD uses 3.3V, hard drives and addressable RGB lights use 5V, but most other components in your PC use 12V.

Example of a Typical Modern 450W PSU Label

An example of a typical modern 450W PSU label from an EVGA 450 BR would show that it delivers its full rated 450W on its 12V rail, plus up to 120W combined on its 5V and 3.3V rails. This would easily be sufficient and run in a good efficiency range, ranging from 40-70%, with around 60% being ideal when your PC is under full load.

However, older PSUs which deliver less 12V power may not be suitable for your build.