120Hz vs. 240Hz Refresh Rate

A 240Hz display refreshes twice as often as a 120Hz display, cutting frame time from about 8.3ms to 4.2ms. In practice, that extra speed mainly matters if your PC and games can actually stay well above 120fps; otherwise 120Hz is usually the smarter buy.

That is the evidence-backed way to look at it. Microsoft's display guidance explains what refresh rate does, LG's current support material shows that higher modes depend on the monitor, cable, and GPU, and current product pages show 120Hz and 240Hz models are both common but built for different priorities.

Table Of Contents

Quick comparison

Factor	120Hz	240Hz
Refresh interval	About 8.33ms per refresh	About 4.17ms per refresh
Best fit	General gaming, everyday use, many console setups	Competitive PC gaming where high frame rates are realistic
Hardware demand	Easier to drive consistently	Needs more GPU and CPU headroom to matter
Connection risk	Usually simpler to hit full speed	More likely to be limited by cable, port, or resolution choices
Practical downside	Less headroom for esports-focused play	Extra speed can be wasted if your system does not stay above 120fps

What the raw difference actually is

Microsoft defines refresh rate as how many times per second the image updates. That means 120Hz updates 120 times per second and 240Hz updates 240 times per second. The useful math is the interval between refreshes: 120Hz is about 8.33ms per refresh, while 240Hz is about 4.17ms.

That is why 240Hz can look cleaner in fast motion. The screen simply has more opportunities each second to show the next frame.

When 120Hz is enough

120Hz is already a major step up from 60Hz for scrolling, general gaming, and many console setups. Sony's PS5 support guide says PS5 supports 120Hz output on compatible displays, and the company's own gaming monitor page treats 120Hz as the console target while reserving up to 240Hz for compatible PC and Mac devices.

If you mostly play single-player games, mixed genres, or titles that do not sit above 120fps for long stretches, 120Hz is usually where the practical win starts to flatten out.

When 240Hz is worth it

240Hz makes the most sense for fast competitive PC play. LG's current 240Hz monitor page and support guide both frame high refresh as a performance feature tied to supported connections and capable hardware.

But higher Hz is not magic by itself. An NVIDIA research brief found that lower end-to-end latency mattered more than refresh rate above 60Hz once latency was controlled, with high refresh still providing a smaller benefit for some tracking tasks. That is a useful reality check: 240Hz helps most when the rest of the system is also fast.

Hardware and cable requirements matter more at 240Hz

LG's support library says 120Hz-and-above modes may depend on the cable, the GPU and CPU, and the specific monitor. LG specifically calls out DP 1.4 or HDMI 2.0 or higher for some high-refresh setups, and its supported-mode examples show that the exact resolution-and-refresh combination changes by model.

So do not buy by the "240Hz" label alone. Check the actual supported refresh rate at your intended resolution, on the port you plan to use, with the hardware you already own.

240Hz does not automatically mean a better overall display

A faster panel can still be the wrong pick if it gives up the things you notice more: resolution, panel type, HDR behavior, color coverage, text clarity, USB-C, or VRR support. Compare complete spec sheets, not just the biggest Hz number.

For example, LG's current 120Hz monitor page markets 120Hz as a work-and-play upgrade, while its 240Hz models are clearly positioned around competitive responsiveness. Different priorities, not a universal winner.

Battery life and everyday use

Microsoft's battery-saving guidance says higher refresh rates use more power. On laptops, that matters. Windows 11 also supports Dynamic Refresh Rate only when the hardware supports VRR and at least 120Hz, which is another sign that 120Hz already covers a lot of smooth-but-practical territory for daily use.

Simple buying checklist

Choose 120Hz if you want a clear upgrade for everyday use, console play, or PC gaming that often stays at or below 120fps.
Choose 240Hz if you mainly play competitive PC titles and your hardware can keep frame rates high enough to use it.
Check the monitor's exact port and resolution limits before buying; high-refresh support is model-specific.
Prefer a monitor with VRR support if your frame rate moves around a lot.

Bottom line

For most people, 120Hz is the better balance of smoothness, compatibility, and practicality. Move to 240Hz when speed is the priority and your PC can actually feed it; otherwise you are paying for headroom you may not see.