HDMI 2.1 TV Buying Guide for Xbox Series X 4K120Hz

HDMI 2.1 is starting to become the baseline for high-end 4K TVs aimed at Xbox Series X and PlayStation 5 users, with a clear focus on 4K at up to 120Hz, variable refresh support, and faster response. The practical takeaway is simple: if your TV doesn’t already include HDMI 2.1, you’re unlikely to get the full feature set that newer consoles are designed to use.

HDMI 2.1 vs. HDMI 2.0: what changes for gamers

HDMI 2.1 is backward compatible with HDMI 2.0—everything an older standard can do, HDMI 2.1 can also do. The catch is that to use HDMI 2.1 “in full,” all connected devices need HDMI 2.1 support. The guidance also notes that you may need a newer cable marked “G48,” and that HDMI 2.1 uses a newer HDCP 2.3 encoding for playback of copy-protected content.

Higher refresh rates: HDMI 2.1 enables high frame rate output of 120Hz at native 4K, commonly referred to in TV terms as HFR 120.
Higher resolutions: It supports 8K and 10K resolutions at 60Hz.
VR and mixed reality: HDMI 2.1 is described as well-suited for virtual reality, with a specific mention of “Windows Mixed Reality” for Xbox Series X.
Dynamic HDR: Instead of HDR being fixed for an entire movie, dynamic HDR can be determined per scene (and is framed as an advantage of the newer approach).
HDR formats: HDMI 2.1 is said to support Dolby Vision and HDR up to 12-bit, as long as the TV manufacturer implements those formats.

For gameplay specifically, the most important feature called out is VRR (Variable Refresh Rate). The text highlights implementations using AMD FreeSync and/or NVIDIA G-Sync to keep refresh behavior variable and reduce artifacts like tearing or other frame drops. It also references Quick Frame Transport (QFT), which is claimed to cut response time to up to 1 ms, targeting minimal delay between controller input and the TV’s signal.

On the audio side, the source also points to eARC for automatic recognition of object-based audio formats such as Dolby Atmos and dts:X via HDMI 2.1. It adds that your AVR must also support eARC.

What to look for when buying a 4K TV for Xbox Series X (and PS5)

If you’re shopping for a 4K TV intended to stay current, the key requirement is that the television already includes HDMI 2.1. The list below is presented as the “must-have” set for running properly with Xbox Series X features.

Native 4K panel refresh up to 120 FPS
HDR formats: HDR10+, HDR10 Pro, and Dolby Vision
HDR gaming support: NVIDIA G-Sync, AMD FreeSync, and HGiG
VRR support
ALLM (Auto Low Latency Mode)
eARC support
Low response time: best case around 10 ms

For players targeting every option on this list, the guidance recommends focusing on LG OLED models. It notes that the LG OLED C9 is described as hard to find (“everywhere sold out”), leading to a recommendation for the LG CX line for the 2020 window, specifically citing HGiG support for the CX 4K TV.

120 FPS: how to confirm a TV can actually display it

To hit 120 frames per second, the guidance stresses that the TV must support 120 FPS at native 4K. It provides an example of what to look for in the video decoder support description, including lines such as:

“HEVC (H.265): 4K@120p with 10 Bit”
“VP9: 4K@60p with 10 Bit”
“AV1: 4K@60p with 10 Bit”

In that example, the TV would be handling 4K at 120fps alongside HDR10. The text also warns that some older TVs may offer 120Hz but require dropping resolution to 1080p to do it.

Why HDMI 2.1 isn’t always treated as “48 Gbit/s” in TVs

The source explains that “pure” HDMI 2.1 can reach 48 Gbit/s, but that TV manufacturers have agreed to cap it at 40 Gbit/s. The stated rationale is that native sources for the maximum bandwidth use cases—specifically framed as 10K at 60Hz—are not expected to appear for consumers for many years, while the saved resources can go toward better chips and a faster smart interface experience.

LG OLED positioning and the recommendation cut

A major conclusion in the guidance is that, for the complete Xbox Series X checklist, LG is treated as the only viable option at the time. It specifically calls out that the other mentioned brands—Samsung, Sony, and Panasonic—do not provide the full combination described, and therefore the recommendation list is said to shrink dramatically.

The text also addresses OLED downsides and attempts to rebut common concerns:

Burn-in and loss of brightness are dismissed as myths for “newer models,” with the claim that proper handling prevents burn-in and that brightness does not decline.
The “real” downside is described as reflections. The guidance says OLED is best enjoyed in a darker room and that sunlight or overhead lamps can create distracting reflections.

For users who want to avoid that reflection problem, the guidance suggests considering Samsung QLED with a VA panel or LG IPS NanoCell panels—while noting that these alternatives require compromises that don’t match what OLED can deliver with an Xbox Series X setup.

Premium LG OLED models highlighted for the 2020 buying window

The guidance frames its top picks as OLED options and lists LG OLED models with approximate pricing noted for August 2020. Prices shown are “circa” estimates and vary by retailer.

LG OLED B9D — 55-inch — ~€1,200
LG OLED BX9LB — (price listed as ~€1,400)
LG OLED B9D — 65-inch — ~€1,700
LG OLED CX9 — 48-inch — ~€1,600
LG OLED CX6 — 55-inch — ~€1,500
LG OLED CX9 — 55-inch — ~€1,900
LG OLED CX9 — 65-inch — ~€3,000
LG OLED CX6 — 65-inch — ~€2,700
LG OLED CX9 — 77-inch — ~€7,000
LG OLED GX9 — 55-inch (retailer listings mentioned)
LG OLED GX9 — 65-inch (retailer listings mentioned)

It also adds a broader sizing suggestion: for the strongest gaming focus, it advises that a 48-inch OLED is a better fit if you want to avoid price and availability constraints, while recommending an 8K TV if you plan to go beyond 77 inches.

Finally, the guidance ties the entire buying logic back to HDMI 2.1 bandwidth and features: it claims HDMI 2.1’s transmission rate (and the associated feature set) is designed to better support fast motion gameplay, improving fluidity, reducing latency, and reaching response figures that previously were associated more with monitor-class displays.