If you‘re looking for the ultimate smooth 4K gaming experience, a high refresh rate of 120Hz is vital. But not all 4K Ultra HD televisions actually support gaming at the coveted 4K resolution with 120 frames per second (fps). This largely comes down to HDMI ports and processing power. Only newer 4K TVs with HDMI 2.1 inputs can accept and display a 4K 120Hz signal from today‘s high-performance gaming consoles and PCs.
To understand why, we have to dive into the technical differences between resolution and refresh rate.
Resolution Versus Refresh Rate
A TV‘s resolution determines the number of pixels on the screen horizontally and vertically. Standard 4K UHD resolution is 3840 x 2160 pixels, meaning about 8.3 million total pixels – 4 times greater than 1920 x 1080 (1080p) resolution. This gives 4K TVs incredibly sharp image quality especially on larger screens.
Refresh rate, also called the "Hz" value, is completely separate from resolution. This number specifies how many times per second a TV panel can update with new image data. A 60Hz screen refreshes 60 times per second, while 120Hz does so 120 times per second.
So for gaming, you want both high resolution for visual detail AND a fast refresh rate for smooth motion clarity. When paired together, 4K resolution and 120Hz refresh rate make for an incredibly immersive gaming experience.
According to the Consumer Technology Association, 4K 120Hz TV adoption reached over 33% of units sold in 2022, up from less than 12% in 2021. There has been swift market movement towards 4K TVs that can handle next-gen gaming needs.
Why 120Hz Refresh Rate Matters
For movies and most TV content, a 60Hz refresh rate is perfectly fine. But for fast on-screen motion like video games and sports, 120Hz makes a huge difference. By showing up to 120 FPS, the TV can display twice as many frames each second compared to 60Hz. This delivers silky smooth motion with no discernible blur.
4K 120Hz is especially impactful for competitive online multiplayer games, where split-second reactions are vital. The super fluid 120 FPS visuals allow you to accurately track fast-moving objects like players and vehicles. Many pro gamers consider 120Hz to be the bare minimum for responsive high-level play.
While the latest PlayStation 5 and Xbox Series X consoles can power games with 120 FPS frame rates, you need a compatible 4K TV to fully display this performance. This is where HDMI 2.1 ports come in.
HDMI 2.1 – The Key to 4K 120Hz Gaming
To transmit the full bandwidth required for 4K 120Hz, a HDMI 2.1 connection is necessary between your console or PC and the TV. HDMI 2.1 has nearly 3x the data bandwidth capacity of the previous HDMI 2.0b standard – up to 48 Gigabits per second (Gbps) versus 18 Gbps.
Bandwidth determines how much uncompressed video and audio data can be pushed through the cable to your display. While HDMI 2.0b can handle 4K video at 60Hz just fine, it tops out there and can‘t deliver 4K 120Hz. Only HDMI 2.1 has enough headroom for 4K 120Hz or higher.
Here are the gaming performance differences between HDMI versions:
| HDMI Version | Max 4K Resolution | Max Refresh Rate |
| 1.4 | 4K 30Hz | 60Hz |
| 2.0 | 4K 60Hz | 60Hz |
| 2.1 | 4K 120Hz | 120Hz |
According to Display Supply Chain Consultants, over 80% of 4K TVs shipped in 2022 have at least one HDMI 2.1 port, compared to only 30% in 2021. More HDMI 2.1 ports allow you to connect multiple gaming consoles or PCs simultaneously while retaining full 4K 120Hz capability.
In addition to higher bandwidth, HDMI 2.1 provides other enhancements like variable refresh rate (VRR), auto low latency mode (ALLM), and enhanced audio return channel (eARC) to optimize the gaming experience.
Real-World Gaming Performance
Of course, achieving 4K 120Hz requires a capable gaming PC or console too. While the PlayStation 5 and Xbox Series X aim to support 4K 120fps, their actual performance varies significantly between games. Demanding AAA single-player titles rarely hit 120 FPS outside of competitive multiplayer modes.
According to extensive analysis by Digital Foundry, here are some real-world examples of 4K gaming performance on the latest consoles:
| Game (Console) | Resolution | Frame Rate |
| Forza Horizon 5 (XSX) | 4K | 60-80 FPS |
| Halo Infinite (XSX) | ~1440p | 90-120 FPS |
| Ratchet & Clank: Rift Apart (PS5) | 1584p | 30 FPS (60 FPS mode) |
| Call of Duty: Vanguard (PS5) | 4K | 100-120 FPS |
To maintain high frame rates, some games employ dynamic resolution scaling, meaning they lower the resolution slightly from native 4K in demanding scenes while trying to stick close to 120 FPS during gameplay.
Ultimately, a 120Hz display provides headroom for noticeably smoother performance even if not every game fully hits 4K 120fps. Variable refresh rate also helps minimize stuttering and screen tearing when frame rates fluctuate.
Input Lag & Calibrated Settings Are Also Key
Input lag – how long it takes for your button press to register as an action on-screen – is another key gaming performance metric influenced by the display. Lower input lag means a more responsive feel.
Here are input lag measurements for some popular 4K 120Hz TVs from RTings testing:
| TV Model | 4K 60Hz Input Lag | 4K 120Hz Input Lag |
| LG C2 OLED | 8.5 ms | 5.5 ms |
| Samsung QN90B Neo QLED | 9.2 ms | 5.6 ms |
| Sony X90K | 13.7 ms | 6.4 ms |
Enabling Game Mode provides the fastest input lag by minimizing image processing. But you also want calibrated picture settings – a top priority is disabling motion smoothing or the "soap opera effect", which increases input lag. Settings like color temperature, gamma, and black level also impact gaming image quality. Experts at THX recommend optimal TV calibration guidelines for gamers.
There are often some simple tweaks that can really optimize your TV‘s gaming performance and picture quality. As an avid gamer myself who does a lot of testing with the latest displays, I‘m happy to share recommended settings and answer any questions!
The Future – 8K 120Hz & Beyond
If you want to be fully prepared for the future, the new Ultra High Speed HDMI cable standard finalized by the HDMI Forum in late 2022 supports up to 48 Gbps bandwidth. This opens the door for 8K 120Hz and 4K 240Hz capabilities.
However, we are a long way off from 8K gaming becoming mainstream. Today‘s GPUs struggle to deliver high frame rates even at 4K, let alone 8K. But for technology enthusiasts eager to adopt the latest cutting-edge display advancements for home theater or gaming, it‘s exciting to consider the possibilities down the road.
Ready for Smooth 4K 120Hz Gaming?
In summary, not all 4K TVs can do 4K 120Hz – you need the latest models with HDMI 2.1 ports. While achieving the full 120 FPS performance still depends on your hardware, a 120Hz display provides a fantastic fluid gaming experience. Brands like LG C2 OLED, Samsung QN90B Neo QLED, Sony X90K, TCL 6-Series, and Hisense U8H now offer relatively affordable 4K 120Hz options.
I hope this detailed guide clearly explains the technology behind achieving smooth 4K 120Hz gaming. Let me know if you‘re considering upgrading your setup and have any other questions! Happy gaming!
