I recently upgraded from an RTX 2060 Super to an RX 9070 XT OC while keeping my older Seasonic FOCUS Plus 650W 80+ Gold power supply. Under heavy GPU load, the computer suddenly shuts off completely. In Indiana Jones and the Great Circle, it powers down within seconds of loading at maximum settings, and Star Wars Battlefront 2 causes a similar shutdown when increasing the resolution. Afterward, pressing the power button does nothing until I turn the PSU switch off, wait a few seconds, and turn it back on. The RTX 2060 Super never caused this problem in the same system. Could the PSU's over-current or over-power protection be tripping because of GPU transient spikes? Should I replace it with a 750W, 850W, or 1000W unit? My other components are a Ryzen 5 7600X, Noctua NH-U12S cooler, A620M Gaming X motherboard, and 32GB of DDR5-5200 memory.
3 Answers
An 850W supply is generally the sensible target for this setup. The 9070 XT can draw over 300W, and some factory-overclocked models can approach 400W during demanding workloads. A 1000W unit is fine if the price difference is small, but it is not necessary for a Ryzen 5 7600X unless you want substantial upgrade headroom.
The 650W unit is below the usual recommendation for an RX 9070 XT. The instant shutdown followed by needing to toggle the PSU strongly suggests a protection circuit is tripping, although a failing PSU or cabling issue could also cause it. Reinstalling the 2060 as a test would help confirm that the problem follows the new GPU. For a replacement, choose a good-quality 850W unit; 750W is the minimum commonly recommended, while 850W gives more room for transient spikes and future upgrades.
You can temporarily reduce the GPU power limit by roughly 20–30% to see whether stability improves. Undervolting may also reduce power use, but it is not always stable on every card. Treat that as a diagnostic or temporary workaround rather than a substitute for an appropriately sized PSU.
The rest of the system is a Ryzen 5 7600X, A620M Gaming X motherboard, 32GB of DDR5-5200, and a Noctua NH-U12S cooler.