Monitor Simulator

144 Hz vs 240 Hz: when is the upgrade worth it?

On IPS only moderately: at 960 px/s blur drops from 12.7 to 10 px, because pixel response time stays the same. A 240 Hz OLED gets down to 4.1 px. Both need around 240 fps.

Settings

960 px/s
on screen; your eye tracks the object
Below the refresh rate, each frame stays on screen longer.
Each frame lights up for only about 1 ms (ULMB, DyAc, BFI).

What your eye sees

LCD (IPS, VA)OLED

Still imageReference
144 Hz IPS12.7 pxHold time 6.9 ms
240 Hz IPS10 pxHold time 4.2 ms
240 Hz OLED4.1 pxHold time 4.2 ms

The images are still captures of what your eye sees while tracking the object. That is why your own monitor shows them correctly, even at 60 Hz. Response times are class values: IPS 5 ms, VA 9 ms, OLED 0.1 ms.

Why 240 Hz does less on IPS than you might expect

From 144 to 240 Hz the hold time drops from 6.9 to 4.2 ms, so pure hold blur shrinks by 40 %. An IPS panel adds its pixel response time, though, and that stays the same. At 960 px/s, blur therefore only drops from 12.7 to 10 px.

A 240 Hz OLED switches practically instantly and gets down to 4.1 px at the same speed. At 240 Hz, the big step comes less from the hertz than from the panel.

Both need matching fps: if your game only delivers 144 fps, a 240 Hz monitor also shows each frame for 6.9 ms.

All formulas and assumptions

Questions about 144 and 240 Hz

Is a 240 Hz IPS worth it over 144 Hz?

A little. In fast motion like a shooter turn at 3200 px/s, blur drops from 42 to 33 px, when scrolling from 12.7 to 10 px. Noticeable, but not a leap like from 60 to 144 Hz.

What if my game only reaches 144 fps?

Then the 240 Hz monitor does nothing for blur: each frame still stays 6.9 ms, which gives the same 12.7 px at 960 px/s as a 144 Hz IPS. At 180 fps it is 11.3 px.

Is a 144 Hz OLED sharper than a 240 Hz IPS?

In motion, yes. A 144 Hz OLED reaches about 6.8 px at 960 px/s, a 240 Hz IPS 10 px because of its response time. The OLED holds each frame longer, but it has almost no response time.