AMD has finally caught up to Nvidia's latest DLSS technologies with its recent FSR 4 update. For years, the Green Team have dominated upscaling, delivering near-native quality while boosting frame rates. Nvidia took the AI route from the start, training its neural networks on massive datasets, so each iteration improved automatically, even without manual intervention. FSR, by contrast, relied on traditional techniques — until this year, when FSR 4 finally made the jump to an AI-driven approach as well. Now, FSR 4 sits between the Transformer-based DLSS 4 and the older DLSS 3, which is to say, it’s very good. Unfortunately, the strength of any upscaler depends on adoption, and the Red Team still lags behind.
Fortunately, third-party (and often open-source) solutions are abound, if you know your way around a few files and repositories. One such app is OptiScaler — previously known as CyberXeSS — and it works to replace upscalers in a game with a different one that might be better in certain scenarios. For instance, if the game supports FSR 2 and was never updated beyond that, OptiScaler can take that FSR 2 input and convert it to DLSS, XeSS, or upconvert it to a newer version of FSR. And now, it supports FSR 4... as long as the game isn't running on Vulkan API or needs an anti-cheat. Apart from replacing upscalers, OptiScaler can also, by extension, replace frame-gen tech and even handle anti-lag features like Nvidia Reflex.
This means that any game with older FSR or DLSS tech is now technically FSR 4-compatible. We use the word "compatible" here on purpose because "FSR 4-ready" is a bit of a stretch as there is no guarantee you'll have a stable experience. Firstly, it's not a simple toggle that you can enable in some GUI. You have to manually tweak files for every single game, and then further mess around with some settings in order to get the best experience possible. This is before installing FSR 4 in the game's directory, individually, which will be different for every game. It's certainly not convenient, but for a free solution that modernizes upscalers in a wide variety of games, it can be a worthwhile tradeoff for many.
There are only about 65 games that support FSR 4 natively, and most of them are obscure titles. In contrast, over 125 games have DLSS 4 (with frame gen) as of May 2025, alone. With OptiScaler, you can now take that number way higher on the AMD side. All you need is a game with FSR 2 and above, or DLSS 2 and above, and OptiScaler will do the magic to replace that with FSR 4. Of course, you need an RX 9000-series card in order to even get FSR 4 as only those GPUs have the necessary hardware (AI accelerators) for it. On top of that, the game must not need anti-cheat software to run in the background or use the Vulkan API, as FSR 4 does not support Vulkan yet.
As long as you meet those prerequisites, and you're comfortable configuring a few options yourself — moving around DLLs and such — FSR 4 can be all yours, ever before AMD seems to start caring about it on a serious level. It's funny because all the hard work is already behind them, they've made the upscaler we always wanted but stopped at the final step where you actually make the tech prevalent. If the community with barely any resources can do it, a billion-dollar corporation should certainly be able to as well. For now, though, this is our best bet, without spending money on alternatives like Lossless Scaling.
