LG UltraGear 27GX790B-B review

Display

OLED lets individual pixels switch off, so a bright object can sit against a dark background without the backlight halo of an LCD. LG’s newer Tandem panel builds on that strength, and RTINGS found brighter output and improved color purity compared with the older 27GX790A-B. ¹

The matte surface spreads reflections rather than leaving them sharply defined. That can be welcome opposite a window, although controlling room lighting still helps. The 27-inch size is comfortable for a normal desk, while the 1440p resolution favors easier-to-drive games over the finer text and larger working area of a 4K monitor.

LG specifies 335 nits of typical brightness and DisplayHDR True Black 500 certification. Those describe different things; neither should be read as a promise of constant full-screen HDR brightness. RTINGS also found that HDR could look brighter than intended, so spectacular highlights do not necessarily mean the most accurate picture. ¹

Motion & Gaming

The refresh rate determines how often the screen can show a new frame. To get the most from 540Hz, the game and computer need to produce very high frame rates too. Less demanding competitive titles are a more natural fit than a graphically intensive game running near 100fps.

Dual Mode trades detail for speed: 720Hz uses 1280 × 720, not Full HD. It can suit someone who prioritizes tracking movement over crisp scenery, then wants to switch back to 1440p for other games. The display does not create extra game frames just because the faster mode is selected.

RTINGS found very sharp motion, but also distracting flicker when variable frame rates changed rapidly. ¹ A stable frame rate helps make this sort of display more satisfying; VRR support alone does not eliminate every visible fluctuation. LG’s 0.02ms GtG rating describes pixel response under its test conditions, not total input delay.

Connectivity

The two HDMI inputs leave room for a console alongside a computer connected through DisplayPort. USB-C adds another way to connect a compatible laptop, carrying video and USB data through one cable. Check the laptop’s display-output support; a USB-C connector by itself does not guarantee video capability.

The USB hub can keep a couple of peripherals at the screen instead of stretching their cables to the computer. USB-C supplies only 5W, so a laptop still needs its own charger. ¹ A headset connection is also provided, with DTS Headphone:X processing available if you want a virtual surround effect.

For a PS5 or Xbox Series console, the very high PC refresh modes are not the reason to buy this monitor. Its OLED contrast and fast response remain useful, but a 4K screen may be the more rewarding match if sharpness and console use dominate.

Design & Ergonomics

The stand adjusts in all the useful directions, including height and portrait rotation, so you can position the screen without using a stack of books. A compatible monitor arm is another option if you want to reclaim desk space. Rear lighting adds some decoration without changing the picture itself.

As with other OLED monitors, long-term use with persistent static elements carries burn-in risk. Use the built-in care functions and let the screen sleep when it is idle. The standard US specification lists two years of parts-and-labor coverage; that statement alone is not a verified promise of burn-in coverage.

There is one verified US hardware configuration, 27GX790B-B.AUS. The 27GX790A-B is the earlier 480Hz model, not another finish of this monitor.

Alternatives

The Alienware AW2725DF keeps the same 1440p class with a 360Hz QD-OLED panel. If your games rarely approach that rate, the LG’s extra refresh headroom may make little practical difference. The ASUS PG32UCDM Gen3 goes in another direction: a larger 4K, 240Hz screen with more room for work and detailed games.

Compared with the preceding LG 27GX790A-B, the new panel, 540Hz native mode and 720Hz option are meaningful additions. They make the newer model attractive to a first-time buyer, but someone already happy with 480Hz should have a specific use for those changes before replacing it.

Verdict

The 27GX790B-B makes most sense for a PC player who has already decided that high frame rates matter more than 4K resolution. Its two modes, OLED contrast and flexible connections make it versatile within that purpose. For a broader mix of office work, console gaming and slower-paced games, a lower-refresh 4K display deserves equal consideration.