When you’re shopping for a gaming monitor, response time is everywhere — 1ms, 4ms, 0.5ms. Manufacturers treat it like a race to zero. But the number on the spec sheet and what you actually see during a fast-paced game are two very different things. Here’s what response time actually means, why the marketing figures are misleading, and how to use this spec correctly when buying.
What Response Time Actually Measures
Response time is how long a single pixel takes to change colour. The standard measurement is GtG (gray-to-gray) — the time in milliseconds for a pixel to shift from one grey shade to another. GtG is measured at mid-tones because that’s where LCD panels are slowest.
A second spec you’ll often see is MPRT (Moving Picture Response Time). This doesn’t measure pixel transition speed at all — it measures how long a pixel appears lit during a single frame using backlight strobing. It’s an apparent motion blur spec, not a hardware response time. Many monitors advertise “1ms MPRT” while having a true GtG of 5–7ms.
These two specs are not interchangeable, and mixing them up is the #1 reason gamers feel misled by monitor specs. Check Rtings.com for independent GtG measurements before you buy.
How Response Time Shows Up In-Game
When pixels can’t transition fast enough to keep up with on-screen motion, you see ghosting — a trailing smear behind fast-moving objects. In shooters it blurs enemy models mid-sprint. In racing games it trails the car body. In MOBAs it smears ability effects.
The faster the action and the higher your refresh rate, the more a slow response time is exposed. At 60Hz you have 16.7ms between frames — a 5ms GtG panel has plenty of time. At 144Hz you have 6.9ms, and at 240Hz only 4.2ms per frame. A true 1ms GtG panel is more meaningful at 240Hz than it is at 60Hz.
Response time is separate from input lag (how long the monitor takes to display a signal from your PC) and refresh rate (how many frames per second the display can show). All three interact, but they’re independent specs. For a full breakdown of how these settings interact, see How to Optimize Your PC for Better FPS and PC Game Settings Explained.
1ms vs 4ms — What the Specs Don’t Tell You
In real-world gaming, the difference between a true 1ms GtG and a true 4ms GtG is rarely visible. Both are fast enough that ghosting is a non-issue at 144Hz. The panels that cause visible ghosting typically measure 8–20ms in independent tests — often IPS or VA panels that advertise fast specs but underperform in practice.
| Response Time (GtG) | 240Hz (4.2ms/frame) | 144Hz (6.9ms/frame) | 60Hz (16.7ms/frame) |
|---|---|---|---|
| 1ms | No ghosting | No ghosting | No ghosting |
| 4ms | Minimal ghosting (borderline) | No visible ghosting | No ghosting |
| 8ms | Visible ghosting | Light ghosting | Negligible |
| 15ms+ | Heavy ghosting | Heavy ghosting | Noticeable |
The practical takeaway: if you’re buying a 144Hz monitor, a 4ms GtG panel is fine. If you’re going 240Hz+ for competitive play, look for panels tested at 1–2ms GtG by independent reviewers — not just the spec sheet number.
Panel Types and Their Response Times
Panel technology determines the upper limit of how fast a monitor’s pixels can transition. Overdrive settings and panel engineering can push closer to that ceiling, but can’t exceed it.
| Panel Type | Typical GtG | Strengths | Ghosting Risk |
|---|---|---|---|
| TN (Twisted Nematic) | 1–4ms | Fastest pixels, cheapest 240Hz | Very low |
| IPS (In-Plane Switching) | 1–6ms | Colour accuracy, wide viewing angles | Low–medium (varies by panel) |
| VA (Vertical Alignment) | 4–20ms | Best contrast ratio, deep blacks | Medium–high (dark-to-dark slowest) |
| OLED | 0.1–0.3ms | Near-instant pixels, perfect blacks | Virtually none |
VA panels deserve a specific warning: their GtG spec is often measured at bright-to-grey transitions. Dark-to-dark transitions — common in shadowed game environments — can be 3–4x slower, causing the distinctive “black smearing” effect on VA monitors.
Overdrive: When Faster Isn’t Better
Most monitors include an overdrive setting (sometimes labelled “Response Time”, “AMA”, “TraceFree”, or “MPRT”). Overdrive pushes extra voltage through the pixel to force a faster transition. Set it too high and you get inverse ghosting — a bright halo in front of moving objects that’s often more distracting than the original ghosting it was trying to fix.
The right overdrive setting depends on your monitor and refresh rate. A safe starting approach: test the medium/normal overdrive setting at your target refresh rate. Step up only if you see trailing, and step back if you see coronas or halos in front of objects. Never leave overdrive at maximum without testing it independently.
Independent testing sites measure overdrive at multiple settings — this is the most reliable way to find the sweet spot for your specific panel.
What to Choose for Your Setup
| Setup | What Matters | Response Time Target |
|---|---|---|
| Competitive FPS (240Hz+) | True GtG, not MPRT | ≤2ms GtG (tested) |
| 144Hz gaming (all genres) | Panel consistency | ≤5ms GtG |
| Single-player / RPG / strategy | Colour and contrast > speed | Any GtG — check for VA smear |
| Console gaming (60Hz) | Input lag > response time | Response time non-issue |
| Budget 144Hz | Avoid VA for fast genres | IPS preferred |
Frequently Asked Questions
Is 1ms response time always better than 4ms?
Not necessarily. A tested 4ms IPS panel often performs better than a spec-sheet “1ms” panel where that figure refers to MPRT rather than GtG. Always check independent GtG measurements.
Does response time affect input lag?
No. Input lag is how long the monitor takes to process and display a signal from your GPU. Response time is how fast pixels change colour after they receive that signal. Both matter for gaming feel, but they’re separate specs.
Is OLED worth it for gaming?
If ghosting elimination is the goal, OLED wins at 0.1–0.3ms GtG. The trade-off is burn-in risk with static UI elements (health bars, minimaps) and a higher price. For competitive play at a monitor-class price, a fast IPS at 1–2ms GtG is a practical alternative.
Can overdrive fix a slow panel?
Overdrive can push a panel closer to its physical response limit, but it can’t exceed it. A VA panel with 15ms dark-to-dark transitions won’t become a 1ms panel with overdrive — and aggressive settings will add inverse ghosting on top of existing smear.
What’s the difference between GtG and MPRT?
GtG (gray-to-gray) measures actual pixel transition speed. MPRT (Moving Picture Response Time) measures perceived motion blur using backlight strobing and is not a true hardware response time. MPRT figures are typically lower and used for marketing.