What are DLSS and FSR? How upscaling gives you more FPS

Modern games are heavy. A 4K screen has about 8.3 million pixels, and the graphics card has to colour every one of them, many times a second. Upscaling is a trick that lets the card draw fewer pixels and stretch the picture to fill your screen. It is one of the cheapest ways to get more frames per second, and it is now built into most big games.

What upscaling actually does

Your screen has a fixed number of pixels, called its native resolution. Normally the game draws at exactly that resolution. With upscaling on, the game draws at a lower internal resolution (say 1440p on a 4K screen), then a clever program enlarges the result to 4K. Drawing fewer pixels means less work, so the frame rate goes up.

The key word is clever. A plain stretch makes everything soft and blocky. The modern upscalers use extra information from the game, such as motion and the previous frames, to rebuild fine detail. That is why a good upscaler can look much closer to native than the pixel count suggests.

Try it: render fewer pixels, keep the screen size

Your screen

Upscaler mode

Stretch method

Game draws at–

Pixels drawn vs native–

Pixels saved–

The scene is drawn small, then stretched to the preview (a lower-resolution screen starts coarser). Zoom in on the thin lines and the text. Real upscalers like DLSS and FSR do far better than this simple stretch.

Notice how the numbers behave. Quality mode draws only about 44% of the native pixels, and Performance mode draws just 25%. The saving grows fast because pixels are counted in two directions: halving the width and the height leaves a quarter of the pixels.

The modes, in plain words

Most upscalers offer the same ladder of presets. The scale factors below come from AMD's FSR documentation and match the usual DLSS render scales: Quality draws at roughly two thirds of the width and height, Balanced at about 58%, Performance at half, and Ultra Performance at one third.

Mode	Draws at (on a 4K screen)	Best for
Quality	2560 × 1440	Looks close to native; a safe first choice
Balanced	about 2260 × 1270	A middle step when Quality is not enough
Performance	1920 × 1080	Big FPS gain; fine detail starts to suffer
Ultra Performance	1280 × 720	Last resort, mostly for 4K on weaker cards

The lower the starting resolution, the less the upscaler has to work with. That is why upscaling looks better on a high-resolution screen: Performance mode on a 4K display starts from 1080p, while Performance mode on a 1080p display starts from 540p, and that looks noticeably softer.

DLSS, FSR and XeSS: who makes what

There are three big names. DLSS is made by NVIDIA and needs a GeForce RTX card. FSR (FidelityFX Super Resolution) is made by AMD and is designed to run on a wide range of graphics cards, not only AMD's. XeSS is Intel's version. A game only offers the ones its developers added, so open the graphics menu and see what is listed.

You may also see frame generation next to these. It is a different feature: it inserts extra frames between real ones to make motion look smoother. It does not make the game respond faster, so treat upscaling and frame generation as two separate switches.

When to use it, and when to skip it

Turn upscaling on when your frame rate is below what your screen can show and you would otherwise have to cut settings. Try Quality first and step down only if you need more frames. If the game already runs smoothly at native resolution, leave it off, since native is always the cleanest picture.

Watch for trade-offs: thin lines can shimmer, fast-moving objects can leave faint trails, and small text in the picture can look soft. Menus and the on-screen interface are usually drawn at full resolution, so they stay sharp.