LG 27GN950-B 4K 144Hz Monitor Review: One Fast Pixel Mover

One of the fastest 4K monitors we've ever tested

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LG 27GN950-B
Editor's Choice
(Image: © LG)

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Uncalibrated – Maximum Backlight Level

The LG 27GN950-B is one of only a handful of 144 Hz 4K monitors we’ve reviewed. To compare it, we’ve rounded up the Acer Predator XB273K, Acer Predator X27, Asus ROG Strix XG27UQ and Asus ROG Swift PG27UQ. Offering similar performance but at 1440p resolution is the Samsung Odyssey G7 32-Inch (C32G75T).

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LG 27GN950 Charts
(Image credit: Tom's Hardware)

SDR brightness isn’t a problem for any of these screens but the LG almost takes the crown with over 458 nits peak. This is more than enough light for any environment, and it has the unfortunate side effect of a high minimum level. Zeroing the backlight only takes the 27GN950-B down to 89 nits. This is a bit too bright for dark spaces like editing suites and post-production bays.

The high black level is no surprise given the backlight intensity and the resulting static contrast is just average at 1034.7:1.

After Calibration to 200 nits

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LG 27GN950 Charts
(Image credit: Tom's Hardware)

Contrast remains the same after our calibration (see our recommended settings on page 1) with just average-for-IPS black levels. But turn on Local Dimming and the score more than doubles to 2331:1. The biggest potential contrast comes from the Asus PG27UQ and its FALD backlight. Engaging its local dimming feature takes its score to over 17,000:1 for SDR.

ANSI contrast is unaffected by the Local Dimming feature. We measured a native intra-image ratio of 888.3:1, a little below average. In practice, real-world content benefits from local dimming with solid black levels and punchy highlights.

Christian Eberle
Christian Eberle
Contributing Editor

Christian Eberle is a Contributing Editor for Tom's Hardware US. He's a veteran reviewer of A/V equipment, specializing in monitors. Christian began his obsession with tech when he built his first PC in 1991, a 286 running DOS 3.0 at a blazing 12MHz. In 2006, he undertook training from the Imaging Science Foundation in video calibration and testing and thus started a passion for precise imaging that persists to this day. He is also a professional musician with a degree from the New England Conservatory as a classical bassoonist which he used to good effect as a performer with the West Point Army Band from 1987 to 2013. He enjoys watching movies and listening to high-end audio in his custom-built home theater and can be seen riding trails near his home on a race-ready ICE VTX recumbent trike. Christian enjoys the endless summer in Florida where he lives with his wife and Chihuahua and plays with orchestras around the state.

4 Comments Comment from the forums
  • CXB
    The most recent firmware to the LG 27GN950-B pushes the display rate to 160Hz at 4k (the firmware takes a nervous 30+ minutes to load)
    A very nice monitor, well-suited to DisplayPort, DSC and the new graphics cards coming out (I was lucky to bag an RTX3070)
    Reply
  • Wanderingm00se
    Honestly, if this had an HDMI 2.1 it would have been an instant buy for me running this well. Maybe a refresh next year will have it. Got a series X as video card prices in Canada are insane right now if available and consoles are almost readily available and are cheaper than US pricing after conversion.
    Reply
  • tomy_12
    I heard with this monitor cannot cancel the option that the monitor will go to deep sleep, is kind of big let down when the monitor fall a sleep and can't wake up. I don't want my monitor to fall a sleep, I can make the pc set to sleep mode alone. would be nice if you can mention it in the review.
    Reply
  • CXB
    Well, you may have heard that, but I've just left my PC and my LG 27GN950 alone for 4 hours, and as soon as I hit my space bar on the keyboard, everything just woke up where it had left off.

    What I do find is that sometimes, with a second monitor, the GPU gets in a twist. But that's not a problem related to this monitor.
    Reply