Watch out, Nvidia: AMD's FSR 4 tech offers a big leap for PC games – but there's a catch

An AMD Radeon RX 9070 XT made by Sapphire on a table with its retail packaging.

• AMD's FSR 4 performance is slightly weaker than FSR 3, based on new FidelityFX SDK 2.0 demo test
• The performance difference is only 5%, which isn't significant, but can be at much lower frame rates or weaker GPUs
• FSR 4 may still be the best choice for RDNA 4 GPU users

AMD's FSR upscaling technology has come a long way in delivering excellent performance and visual quality, with the leap from FSR 3 to FSR 4 serving as proof of that, especially on one of the best GPUs on the market – but there's a catch.