FSR is basically part of a software driver for a GPU.

FSR, XESS, DLSS (AMD, Intel, Nvidia) are all their software solutions for taking a lower resolution rendering of a video game, and upscaling it to a higher resolution.

They are all different in how exactly they do this, they all have different visual quirks, oddities, quality.

They are also all designed to work with their own hardware, primarily.

These realtime frame upscaling algos also usually come with an accompanying Frame Generator… which basically makes a ‘fake frame’ in between ‘real frame’ renders.

This can make your fps go up, but it can also introduce… weird kinds of input latency, other visual oddities, which will tend to be much more noticable and much worse for fast paced, competetive games, but is usually not a problem for slower paced, less intense games.

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What Decky FrameGen does is… short version is that it takes a bunch of that kind of software and essentially hacks it into some games.

Each game is different, each kind of frame upscaler / frame generator is different.

Technically, Decky FrameGen is more or less just a front end to make this work easily on a Steam Deck interface.

Technically, its really pulling from Optiscaler, which is a collection of basically… video game / video driver modders / hackers.

They are writing and tweaking code so that things that should not officially work… do.

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So… maybe think of this as a kind of very, very complicated mod for a video game… and your hardware.

lol

Also, when I say ‘hackers’ I mean that in the sense of … making things that shouldn’t work, work, not in the sense of bad guy bad person who is intentionally fucking up your shit in one or another.

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As to how to use a frame upscaler?

The resolution you set for the game is the ‘target’ resolution. Say 1920 x 1080.

What the upscaler does, is render a frame at… 90%, 80% of that resolution, and then ‘upscales’ it to that full 100% resolution.

When you see modes like ‘Quality’ ‘Balanced’ ‘Performance’ ‘Ultra Perfomance’… basically, you’re going steadily downward to a smaller percentage of resolution that is actually rendered, and then upscaled.

So, a 100% … would basically just be equivalent to… not using an upscaler at all.

This all exists so that you can get more FPS than you otherwise could, for what is, in theory, supposed to be only a small degredation in visual quality.

The problem is that the degredation often ends up being fairly drastic, and the other problem is that… a whole lot of game devs just get or already sloppy, and now their answer to ‘why does this game run/look like garbage’ is ‘buy a graphics card that supports the upscaling tech we designed it for.’

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Now to try to wrap that all around:

If you can hack in support for games and older hardware to run the upscalers, instead… well now, you may not need to actually buy the graphics card, because now, it might kinda work on what you already have.

Apologies for how long this explanation is, but this shit is just actually really complicated.