Enabling AMD's latest upscaler on older Radeon GPUs isn't as difficult as it previously seemed. With a newly discovered trick, one can enable FSR 4 even on RX 6000 GPUs.
By Swapping Two Files in the New Adrenalin Driver, User Demonstrates Improved Visual Quality in Games With AMD RDNA 2 GPUs
A while ago, it was discovered that FSR 4 also works with Radeon RX 7000 GPUs on Windows OS . This method incorporated INT8 model files that leaked from the AMD source code previously, and apparently also worked for RDNA 2, aka Radeon RX 6000 GPUs. However, these GPUs reportedly didn't respond well to the latest upscaler and had noticeable performance impacts, but it looks like someone just fixed it with a simple trick.
It's not the first time someone tried to enable FSR 4 on an RX 6000 GPU , bu