What motion blur reduction is

As an Amazon Associate I earn from qualifying purchases. I earn a small commission from Amazon links, at no cost to you. See disclosure.

Want moving targets to look sharper? That’s what motion blur reduction is for. It flashes the backlight. Each picture stays dark for most of the frame and lights up for a short slice. A moving edge looks cleaner because your eye is shown less of a picture that would otherwise sit still until the next one. The pixel did not get faster.

I play on a 1080p 240 Hz panel for Overwatch and a 1440p 155 Hz panel for everything that wants more pixels, driven by an RTX 5080. For full picks, see the best gaming monitors. Response time is how long the pixel takes to change shade after a new picture starts. A small MPRT number is not that wait. More monitor guides.

The specs below come from NVIDIA, Zowie and ASUS pages, so check the current listing before you buy.

What to check first

Motion blur reduction flashes the backlight. The pixel is a different wait. A second edge, a dim picture, or a smear you already see are not the same problem.

The moving edgeIt smears behind the objectIt has a second edgeIt already looks cleanThe flashThe mode is offThe mode is onNot sure yetThe roomBright enough to wash the screenDim enough that a darker picture is fine

What this means

The picture is held

The backlight stays on for the whole gap, so a moving edge smears while your eye tracks it. A flash shortens that lit time. The picture gets dimmer, and variable refresh usually turns off.

Watch one edge you already know, in the same scene, and change one thing.

Panels worth a look

• DyAc 2, 24.5” 1080p 240 Hz: Zowie XL2546X. Official: Fast TN, 1920×1080 at 240 Hz, typical brightness 320 nits, contrast 1000:1, DyAc 2, VRR listed as yes with DyAc 2 off. Zowie’s DyAc FAQ says DyAc and VRR (G-Sync / FreeSync / Adaptive-Sync) disable each other. XL2546X. What is DyAc / DyAc+ / DyAc 2. XL2546X FAQ. Amazon search for XL2546X
• ELMB Sync, 27” 1440p 180 Hz: ASUS TUF Gaming VG27AQ3A. Official US shop $249.00. Official: Fast IPS, 2560×1440, 180 Hz, 1 ms (GTG), ELMB and ELMB Sync, Adaptive-Sync / FreeSync Premium / G-SYNC Compatible, typical brightness 250 cd/m². ASUS’ ELMB FAQ says ordinary ELMB is fixed-rate only, and ELMB Sync can stay on with VRR, recommended above 120 Hz, and not at the same time as HDR. VG27AQ3A. What are ELMB and ELMB Sync. Amazon search for VG27AQ3A
• ULMB 2, 27” 1440p 360 Hz: NVIDIA’s ULMB 2 page names the Acer Predator XB273U F. Official: 2560×1440, 360 Hz, backlight strobing at the panel’s full refresh. NVIDIA’s enable steps start by turning G-SYNC variable refresh off in the NVIDIA Control Panel, then turning ULMB 2 on in the monitor menu. ULMB 2. Acer ULMB 2 note. Amazon search for Predator XB273U F

The short version: the flash shortens how long the picture stays lit. It usually costs brightness, and it usually turns variable refresh off.

Why a moving picture smears

An LCD holds each frame until the next one is allowed to start. Once the crystals have moved, the backlight stays on, so the same picture sits there for the whole gap. Your eye follows the object. That still image slides across the retina, and the edge looks soft even though the pixel already arrived. That softness is the hold. It is not a slow crystal. NVIDIA’s ULMB 2 write-up calls the same two pieces by name: the visible transition, and the image being held before and after it.

The gap is the refresh schedule. At 60 Hz it is about 16.7 ms. At 144 Hz it is about 6.9 ms. At 155 Hz, the sharper screen I actually use, it is about 6.5 ms. At 240 Hz, the Overwatch screen, it is about 4.2 ms. A higher rate shortens how long each picture is held. A fast pixel on a 144 Hz panel can still look soft in motion because the settled picture was lit for most of those 6.9 ms. Doubling Hertz and frames halves the hold. That is why 240 Hz can look cleaner than 60 Hz on the same fast panel, with the backlight left on.

The other smear is the pixel still changing. A dark trail behind an object is that change, and it belongs to the response-time number, usually a gray-to-gray test of one pair of shades. Motion blur reduction does not finish a shade the crystals have not reached. If the edge is still moving when the light comes on, you see two edges instead of one clean one.

IPS and VA still show up in that trail. A VA panel often finishes a dark change more slowly than a bright one. The flash will light whatever shade is there. It will not finish a pixel that has not changed.

What the flash does

The backlight turns off. The pixel is given the gap to arrive. Then the light pulses, and you see the settled picture for a short time and darkness for the rest. Your eye gets a brief sample instead of the whole held frame, so the tracked edge looks harder. Zowie’s DyAc page is the CRT sentence the other reviews keep repeating: the backlight turns on and off at a fixed point so a moving object does not leave a residual light from the last one.

MPRT is the length of that visible slice. A listing that prints 1 ms MPRT is advertising the flash. It is not promising that every shade changes in 1 ms, and it is not a 1 ms click. Without a strobe, MPRT is mostly the hold: about 16.7 ms at 60 Hz. Blur Busters’ motion-blur-reduction FAQ is the page the other reviews keep citing for that split, and it is the one I will stick to. GtG versus MPRT is the pixel page.

Makers name the switch themselves. The manual is the name.

• ULMB is NVIDIA Ultra Low Motion Blur. The 2015 version, on NVIDIA’s ULMB 2 page, disabled the backlight 75 percent of the time (a 25 percent duty cycle), dimmed a 300-nit panel, and often lowered the refresh rate so the pixels had longer to finish. ULMB 2 strobes at the monitor’s full refresh, claims nearly 2× the brightness of that first version, and uses what NVIDIA calls Vertical Dependent Overdrive so the pulse hits after the scan has settled. Effective motion clarity on that page is refresh rate times one over the duty cycle. A 360 Hz panel at a 0.25 duty cycle is the 1440 Hz comparison they print.
• DyAc is Zowie Dynamic Accuracy. DyAc 2 adds a dual backlight. The XL2546X spec lists flicker-free as yes with DyAc 2 off, and VRR as yes with DyAc 2 off. Those two footnotes are the cost written in the table.
• ELMB is ASUS Extreme Low Motion Blur. The ASUS FAQ, updated 28 January 2026, says ordinary ELMB is backlight strobing at fixed rates such as 85 Hz, 100 Hz, and 120 Hz. ELMB Sync is the version that can run with G-SYNC, FreeSync, or Adaptive-Sync. It still “greatly reduce[s] the overall brightness,” and it cannot run with HDR.

Look in the monitor’s own menu for the blur, strobe, or stabilizer line that page describes. Windows does not have this control. Turning it on does not change the refresh rate you already picked under Settings, System, Display, Advanced display.

Some menus also set how wide the pulse is. NVIDIA’s older ULMB called that pulse width. A narrower pulse is a cleaner edge and a darker picture, because the light is on for less of the frame. Narrow it only while you can still read the scene. If the picture goes too dark for the room, the mode is the wrong tool. The panel is not failing.

On an LCD the trick is the backlight. A panel whose pixels make their own light can insert a black frame instead. Same short sample, different switch.

The double image

A second edge means the flash arrived while the pixel was mid-change. The old shade and the new shade are both lit for that pulse, so a moving object grows a ghost just beside it. That ghost is crosstalk. NVIDIA’s ULMB 2 page uses that word for the double image you get when a single backlight flashes a panel that is still scanning. It is not the soft smear of a held picture, and it is not the halo from overdrive alone.

Overdrive pushes the pixel past the target so it arrives sooner, then pulls it back. Used with a strobe, too hard a push is a common way to get the ghost, because the light samples the overshoot. Change one control. If the second edge appears, step overdrive down, or turn the flash off, and play the same scene. Two changes in one minute will not tell you which one drew the ghost.

Some modes wait until the pixel has settled before they pulse, so the picture can start a little later than with the backlight left on. Do not read a 1 ms MPRT line as the time from a click to the screen. Input lag is that other wait. Zowie’s DyAc FAQ says DyAc does not add input lag because it runs on the monitor and does not sync to the PC. That is Zowie’s sentence for DyAc, not a universal promise for every strobe name.

What you give up

Brightness is the cost you will notice first. The lamp is off for most of every frame A bright room washes out what remains. A dim room hides the loss. If you play with the lights up and the scene is already hard to see, leave the mode off.

Variable refresh changes when the next picture starts, so the panel can meet a frame that arrived early or late. A strobe is timed to a gap that stays put. When that gap moves, the pulse has nothing fixed to aim at. The maker pages agree more often than they disagree:

• NVIDIA’s ULMB 2 how-to: disable G-SYNC variable refresh first, then enable ULMB 2 in the OSD.
• NVIDIA’s Linux driver README says ULMB is a feature “incompatible with VRR.”
• Zowie’s DyAc FAQ: turn VRR on and DyAc turns off; turn DyAc on and VRR turns off. DyAc wants a high, stable Hertz and a matching frame rate. VRR is for the gap when those two numbers drift.
• ASUS ordinary ELMB: cannot stay on with Adaptive-Sync or FreeSync. ELMB Sync is the named exception, recommended above 120 Hz, and it still cannot stay on with HDR.

A listing that does not say both can stay on has not offered both. A badge on the box is not that sentence. NVIDIA has also named G-SYNC Pulsar as a later attempt to strobe while the refresh moves. That is a different product line.

The game’s motion blur slider is a different control. It paints smear into the frame on purpose, so a turn feels heavier. The monitor cannot erase a smear the game already drew, and the game slider cannot flash the backlight. If you wanted a hard edge, turn the game’s blur off in its display menu. Leave the monitor flash for the hold.

The flash does not add frames. A counter at 80 is still about 80 pictures a second. Each of those pictures is lit for less time. The unused room on a 144 Hz panel is still a frame the PC did not draw. FPS monitor notes is the Hertz and resolution page after this one is settled.

Flicker is the other cost some people feel. A strobe is a lamp turning off. Zowie prints flicker-free only with DyAc off. If the pulse bothers your eyes, the mode is finished for you, even if the edge looks cleaner.

When to leave it off

Leave it off when the room is bright and the picture is already too dim. Leave it off when the frame rate moves and you want the panel to follow it. Leave it off when a second edge shows up and one step of overdrive does not clear it. Leave it off when the listing never named a strobe, a DyAc, an ULMB, or an ELMB line.

A moving edge that is already a single clean line, with the backlight steady, does not need the flash. You would be trading light, and usually variable refresh, for a difference you cannot see. I keep two screens because I want 240 Hz at 1080p for Zarya and more pixels at 155 Hz, not because I turned a strobe on.

A dark trail that survives the flash is the pixel, not the hold. More pulse width will not finish a shade the crystals have not reached.

Turn the flash on only when the edge is a hold smear, the room can stand a dimmer picture, and you are willing to give up VRR unless the page named ELMB Sync. More monitor guides.

Common questions

What is motion blur reduction on a monitor?

A mode that strobes the backlight so each frame is shown for a shorter time, making fast motion look sharper. Common names are ULMB, DyAc, and ELMB.

Why does motion blur reduction make my screen darker?

The backlight is off for part of each frame, so less light reaches your eyes. Most monitors raise brightness to compensate, but it's still dimmer.

Can I use motion blur reduction with G-SYNC or FreeSync?

Usually not. Strobing needs a fixed refresh rate, so most monitors turn off variable refresh when blur reduction is on.

Is it the same as the motion blur setting in games?

No. In-game motion blur adds blur on purpose. Monitor blur reduction removes the blur your eyes see on fast motion.