Guide to the world of NVIDIA technology: higher chances of winning with faster response with Reflex – Chapter 1

When we compare the gaming performance of computers, we usually look mainly at frame rates. It tells you how fast the game will run. For action game players, an even more interesting indicator is how quickly the game can react to, for example, when you aim somewhere and shoot. If this goes on for a long time, it may happen that by the time the bullet goes off, the enemy will no longer be in the crosshairs, and instead of another notch in the stat, you’ll just see a texture with a bullet hole on the wall.

That’s why, soon after you start an online fight, in addition to whether the image is too twitchy, sooner or later you will also start to care if you can aim and fire faster than the person who suddenly appears in front of you.

A lot of things have to happen between the click of a mouse button and the flash of a shot on the screen, and during each of them, every part of the chain between the chair and the monitor gets stuck on something for a moment. Mostly it’s units or low tens of milliseconds, but when it adds up, you can get over a tenth of a second, and you don’t have to be a pro gamer to register such a delay. It manifests itself, for example, in the fact that it will seem to you as if the mouse is connected to the computer through a rubber band, and if the response is already very bad, it can cause you problems and hit an open door while running.

The first link in the chain where the control can get delayed is the mouse. Gaming mice with a 1000 Hz sampling rate cost a few hundred, and if you don’t have one, definitely get one. And if you have it, but you haven’t addressed the response speed, be sure to check if it only runs at the classic 125 Hz. A person used to a 1000Hz mouse can already recognize the delay caused by slower sampling by the lazier behavior of the cursor in Windows.

If you have fast input devices solved, the graphics rendering or the monitor can be the biggest obstacle. For classic 60Hz displays, one redraw of the image takes 16.7 ms. At 120 fps it’s just over 8 ms, and at 240 fps you can only get a little over 4 ms. This is also why action game players chase high frame rates. It’s not so much that they feel the game at 300 fps is smoother than at 200 fps, especially if their monitor can’t display images at that rate. Rather, the point is that increasing frame rates means reducing the time required for image rendering and faster response.

With v-sync on, it makes a pretty significant difference on a 60Hz panel if the new image arrives on the display just before the image is redrawn, or right after it. In the first case, it can go to the display immediately, in the second case, it can spend up to 16.7 ms waiting for the monitor to finish drawing the previous image.

With classic LCD panels, it also takes a while for the crystals to roll to the right side. And even if they help themselves with tricks like overdrive. It always takes a few extra milliseconds to render. That would probably not matter so much, the worse thing is that the LCD usually doesn’t redraw perfectly with a single progress, but ghosts remain after the previous image. From a paper response, one millisecond is more like two or three redraws of the screen before the subpixels finally change their mind and get nicely colored.

It can be extinguished faster

In this respect, monitors with OLED displays have an extreme advantage. With them, redrawing the point is an order of magnitude faster; it only takes a few hundredths of a millisecond to turn on or off the dot perfectly, the display response is more prompt and the image in motion is also much sharper thanks to this.

A fresh novelty on the market is a series of displays with new 32″ QD-OLED panels from Samsung. Classic LCDs are incomparable with them in terms of gaming parameters.

Even compared to older OLED panels, they no longer make any compromises in terms of resolution or refresh rate. They offer a solid 32″ diagonal at 4K resolution and a high refresh rate of 240 Hz.

I’m not a pro-gamer, my uncritical enthusiasm for OLED monitors, despite some of their drawbacks, stems more from how OLED behaves compared to LCD when measuring response or slow-motion. So I was really happy that we were able to borrow a monitor to test the effect of Reflex on the response in games AORUS FO32U2P from the Gigabyte menu. I can’t think of any better display currently available that could be used for a measurement where every millisecond will affect the overall response time as well as the size of the measurement error.

Even on a cheap high-speed “camera” with which I record at 1000fps and struggle with quality at low shutter speed and high ISO, there is more to see on that OLED than when I shoot a classic LCD. The image on the recording is clearer and more contrasty, and thanks to the much faster redraw, you can easily see where the image is being redrawed.

OLED displays aren’t perfect either, but from a player’s point of view, the advantages clearly prevail – whether it’s top contrast, extreme viewing angles, refresh rate, or the aforementioned pixel response or input lag of the monitor itself. I will not describe extensive product pages and all technologies, I will only list the basic equipment and parameters:

• Resolution 3840×2160 points at 240 Hz on 31.5″ OLED, 10bit, adaptive v-sync
• 99% coverage of the DCI-P3 color space,
• Jas 250 cd/m² (Typ, SDR APL 100%); 1000 nits (Typ, HDR APL 3%)
• VESA certification DisplayHDR True Black 400, motion sharpness ClearMR 13000
• konektory 2x HDMI 2.1, 1× Displayport 2.1 (UHBR 20, 80Gb/s) in, 1× Displayport 1.4 (HBR3) out, 1× mini DP 2.1 (UHBR 20), 1 x USB Type-C (Alternate Mode; Upstream port; Power Delivery až 65W), 2× USB 3.2 Downstream, 1 x USB 3.2 Upstream, audio jack 1× sluchátka, 1× mikrofon,

When we have the mouse and monitor sorted out, we can get down to optimizations on the side of the PC itself. When creating the Reflex interface, NVIDIA focused on keeping the delays as small as possible during scene processing and image rendering. NVIDIA Reflex SDK is a set of APIs for game developers, which allows not only to reduce latencies, i.e. to speed up the system’s response to input from controllers, but also to measure the length of the response on the side of the computer itself.

When measuring PC response in software in applications using Reflex libraries, you must of course also take into account the delay caused by the peripherals. Applications like FrameView have no way of knowing how long the mouse has been working on analyzing the image from the sensor, or how long it has taken the monitor to render the image after it has arrived from the graphics card.

Reflex works on all GeForces from the GTX 900 model series inclusive. The entire ecosystem and issues surrounding response is discussed on several pages and subpages on the nvidia.com website, something i in Czech.

Reflex can do more than controllers

To a certain extent, the response can be shortened with the help of controllers. But with them, Nvidia can adjust the behavior of the graphics card, but it no longer has the ability to influence at what point the game will read the mouse movement before rendering the image or when the processor starts working with the scene. And that is to be provided by NVIDIA Reflex. If the developers integrate Reflex into the game, they can fine-tune the game engine so that the rendering takes place just-in-time. Rendering of the image then starts literally at the last moment, so that it is completed just before the monitor is redrawn, which can shorten the response time by up to a third.

Since the launch of Reflex, over has made it to the list 110 supported titles and I have no idea if they’re all on it. Others are rapidly increasing due to, among other things, the fact that Reflex is an integral part of the DLSS Frame Generation. In games with frame generation support, it is implemented precisely to reduce the response, which would otherwise be prolonged by the delay of the last rendered frame due to the display of the generated intermediate frame.

When Nvidia Reflex is integrated into the game, in addition to the Reflex On or Reflex Enabled settings, you will often find the Reflex Boost or Low Latency Boost functions in the settings. If the graphics card is not fully loaded, it may reduce clocks to reduce consumption. It’s fine for normal gaming, but if you want peak response times, it’s better if it’s consistently running at maximum clocks, which can speed up frame rendering, and that’s what boost is supposed to provide. It will of course come at the cost of higher consumption.

And how Reflex works in practice, we will see in the next chapter.