Televisions · 2025 · LG

LG OLED77B5PUA (B5, 77-inch)

The LG B5 is the entry model of the company’s 2025 OLED line. The 77-inch version offers a 4K 120 Hz OLED panel, the α8 Gen2 processor, four HDMI 4K 120 Hz inputs, Dolby Vision and webOS 25. In testing, gaming performance and colour were strong, while brightness stayed clearly below the C series.

North American model OLED77B5PUA, 77 inches. The 48, 55, 65 and 83-inch B5s and European B5 models have separate codes; power, dimensions and weight change with size. The B4, B6 and C5 are separate models.

Specifications

SpecificationValue
Display77-inch class (77.4-inch diagonal) 4K OLED; 3840 × 2160

In OLED each pixel makes its own light and can switch off completely, so blacks are much deeper than on backlit LCDs.

Refresh rateNative 120 Hz; VRR up to 120 Hz

VRR matches the screen’s refresh to the frame rate of a console or PC, reducing tearing.

Processorα8 AI Processor 4K Gen2

Picture processing, upscaling of lower-resolution content to 4K and audio up-mixing run on this chip; it sits below the processors in the C and G series.

HDRDolby Vision, HDR10, HLG; Dynamic Tone Mapping Pro; Filmmaker Mode

HDR10+ is not in LG’s list; content mastered in HDR10+ plays as standard HDR10.

GamingFreeSync, G-Sync Compatible, ALLM, HGIG, Game Optimizer; response time under 0.1 ms

ALLM automatically switches the TV to a low-latency mode when a connected console starts a game; HGIG leaves HDR tone mapping to the game itself.

HDMI4 HDMI inputs; all four support 4K 120 Hz, VRR, ALLM and QMS; eARC on HDMI 3

eARC sends audio from the TV’s apps, including Dolby Atmos, losslessly to a compatible sound system.

Other connections2 USB 2.0, Ethernet, antenna/cable input, RS-232C (mini jack)

RS-232C and IP control let home automation systems manage the TV.

WirelessWi-Fi 6E; Bluetooth 5.3

Wi-Fi 6E can use the less crowded 6 GHz band with a compatible router; Bluetooth is used for headphones and speakers.

Audio2.0-channel down-firing speakers; Dolby Atmos; α8 AI Sound Pro (virtual 9.1.2)

Virtual 9.1.2 is processing that tries to create a multi-channel impression from two speakers; there are no real height or rear speakers.

Smart TVwebOS 25; Google Cast, AirPlay 2, Matter; built-in Alexa; Magic Remote MR25

LG promises software updates and feature refreshes under its Re:New program; most apps require an internet connection and an LG account.

Power consumption187 W; 344 kWh per year; standby under 0.5 W

Actual consumption varies with content brightness and picture mode; the annual figure is based on US test conditions.

DimensionsWithout stand 67.7 × 38.9 × 2.0 in (about 172 × 98.8 × 5.1 cm); with stand 67.7 × 41.6 × 12.6 in

The stand is 55.2 inches (about 140 cm) wide; the furniture it sits on must be at least that wide.

WeightWithout stand 50.5 lb (about 22.9 kg); with stand 51.8 lb (about 23.5 kg)

Use the weight without the stand when choosing a wall mount.

Wall mountVESA 300 × 200

The VESA size is the horizontal and vertical spacing of the screw holes on the back; the mount must support it.

In the boxStand, Magic Remote MR25 with batteries, power cable, quick start guide

No HDMI cable is listed.

From the manufacturer

LG presents the B5 with the Alpha 8 AI Processor Gen2, Dolby Vision, Dolby Atmos, NVIDIA G-Sync and a 120 Hz refresh rate. LG US

Strengths and limitations

  • In TechRadar’s test of the 55-inch B5, HDR peak brightness on a 10% white window measured 668 nits in Cinema mode and 637 nits in Standard mode, and 131 and 172 nits full screen; these are almost identical to the B4 and well below the C5’s roughly 1,180 nits. UHDA-P3 colour coverage measured 99.5%. The screen was found clearly reflective in a bright room, and the 20 W two-channel sound lacked bass. Input lag measured 9.1 ms in Game Optimizer’s Boost mode; on an Xbox Series X the input delay setting could not be changed while Dolby Vision gaming was active.

    TechRadar review, 55-inch model; measurements vary with picture mode and firmware.

    TechRadar: LG B5 review
  • RTINGS tested the 77-inch model and says the results also apply to the 48, 55, 65 and 83-inch sizes; it rated brightness as decent with a score of 7.0 out of 10.

    RTINGS review; full text could not be read, a search excerpt was used.

    RTINGS: LG B5 OLED TV review

Owner experiences and issues

  • Most reviews on Best Buy Canada praise picture quality and blacks; negative reviews centre on faults, software and service. DocLocke, Bev H, IanT85 and Lgst1nks say their TVs stopped working or developed lines on screen within four to seven months, and two of them say warranty service took over a month. RODNEYM says they returned the first TV because of horizontal lines and the second keeps dropping its Wi-Fi connection. Bruhsky had to replug the HDMI cable for a device to be detected, Jason Vanwinkle says picture settings change by themselves from app to app, and Janky says apps cannot be used without creating an LG account. Kendra B says the screen looks washed out in a bright room but is fine with blinds partly closed; BENITOH finds peak brightness lower than their old TV.

    The review pool shown on the Best Buy Canada 77-inch listing combines LG.com (US, Canada, UK, Singapore) and promotional syndicated Best Buy US reviews; it includes other B5 sizes and at least one B6 review, which was excluded. Four pages (about 200 reviews) were read, low ratings first. Individual reports; no failure rate was drawn.

    Best Buy Canada: LG 77-inch B5 OLED (OLED77B5PUA) customer reviews

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Sources

  1. LG US: OLED77B5PUA specifications
  2. TechRadar: LG B5 review
  3. RTINGS: LG B5 OLED TV review
  4. Best Buy Canada: LG 77-inch B5 OLED (OLED77B5PUA) customer reviews