MonitorsComputer Monitor

LG 35BN75C Monitor Manual

Setup, everyday use, maintenance and troubleshooting for the 35 in. ultrawide QHD curved IPS-type monitor, with verified specifications.

  • Screen35 in.
  • ResolutionUWQHD ultrawide
  • On-mode power32.4 W
  • Est. yearly cost$16.99

About the LG 35BN75C

The LG 35BN75C is a 35 in. ultrawide QHD curved IPS-type monitor certified under the ENERGY STAR program for displays. Its native resolution is 3440 × 1440 pixels (UWQHD ultrawide), about 107 pixels per inch.

It uses an IPS LCD panel with a rated maximum luminance of 250 cd/m² (nits). Listed signal and data interfaces include HDMI, DisplayPort, and USB. A USB-C port with Power Delivery can charge a connected laptop at up to 90 W while carrying video and data. Other listed equipment includes built-in speakers.

Measured on-mode power is 32.4 W, with 0.09 W in sleep and a total energy consumption (TEC) rating of 100 kWh per year — 2% below the ENERGY STAR limit for a display of this size and resolution.

Specifications

LG 35BN75C specifications
BrandLG
Model number35BN75C
Display typeComputer Monitor
Screen size (diagonal)35.0 in.
Screen area439 sq. in.
Panel technologyIPS LCD
Native resolution3440 × 1440
Resolution classUWQHD ultrawide
Pixel density107 ppi
Maximum luminance250 cd/m²
Enhanced Performance DisplayNo
Signal and data interfacesHDMI, DisplayPort, USB
USB-C with Power DeliveryYes
Maximum USB-C charging power90 W
Built-in speakersYes
Curved screenYes
Power sourceExternal AC adapter
On-mode power32.4 W
Sleep-mode power0.09 W
Off-mode power0.07 W
Total energy consumption (TEC)100.0 kWh/yr
ENERGY STAR TEC limit102.3 kWh/yr
Below ENERGY STAR limit2%
ENERGY STAR Most EfficientNo

Safety information

  • Place the monitor on a stable, level surface. When using a monitor arm or wall mount, choose one rated for the monitor's weight and VESA pattern and tighten it as instructed.
  • Use only the external power adapter supplied with the display (or an identical replacement). An adapter with a different voltage or polarity can damage the monitor.
  • Keep the ventilation openings clear and do not place the display near radiators, heaters or in direct sunlight.
  • Do not expose the display to rain, moisture or spilled liquids. If liquid gets inside, unplug it immediately and have it checked before further use.
  • Unplug the display during lightning storms or when it will be unused for an extended period.
  • Keep fingers clear of the hinge and height-adjustment mechanism when tilting, pivoting or raising the screen.

Setup

Position the 35 in. screen about 30–40 in. (75–100 cm) from your eyes, directly in front of you, with the top line of text at or slightly below eye level. Tilt it back 10–20° and place it at a right angle to windows to minimize glare. For a curved screen, sit near the center of the curve so the edges are equally distant.

  1. Assemble the stand

    Attach the stand or monitor arm while the display is lying face-down on the protective packaging or a soft cloth. Do not press on the screen.

  2. Connect the video cable

    USB-C is the simplest option with a laptop: one cable carries video, USB data and up to 90 W charging power. If your laptop's own charger is rated higher than 90 W, it may charge slowly under heavy load — keep its adapter handy. DisplayPort is generally the best choice for high refresh rates from a desktop graphics card. HDMI works with most laptops, desktops and game consoles.

  3. Set resolution and scaling

    In your operating system's display settings, select the native resolution of 3440 × 1440. At about 107 pixels per inch, a scaling setting around 100% usually gives comfortably sized text; adjust to taste.

  4. Adjust brightness

    Set brightness so a white page looks similar to a sheet of paper under your room lighting — typically 100–150 cd/m² for office work, well below this model's 250 cd/m² maximum. Lower brightness reduces both eye strain and power use.

Using your monitor

Picture modes and color

Use the on-screen display (OSD) menu to choose a picture preset. A standard or sRGB mode is best for office work and web browsing. Avoid "dynamic" contrast modes for photo editing, as they shift brightness with screen content.

Power management

The monitor enters sleep automatically when the computer stops sending a signal, dropping to 0.09 W. Set your computer to turn off the display after 5–15 minutes of inactivity so this happens during breaks. With the power button off, the monitor draws 0.07 W.

USB-C charging and docking

With a USB-C laptop connected, the monitor supplies up to 90 W through the same cable that carries the picture. Many monitors keep the USB-C port powered in sleep so the laptop continues to charge; check the OSD for a "USB charging in standby" option if you want to disable it.

Built-in speakers

Select the monitor as the audio output device in your computer's sound settings; audio is carried over HDMI, DisplayPort, or USB-C along with the picture.

Features

USB-C Power Delivery
Single-cable video, data and laptop charging (up to 90 W).
Built-in speakers
Plays audio from the connected computer or media player without external speakers.

Care and maintenance

WhenWhat to do
WeeklyDust the screen with a dry microfiber cloth using light pressure.
When smudgedPower the display off, then wipe with a microfiber cloth lightly dampened with water. Never spray liquid directly on the screen or use ammonia- or alcohol-based glass cleaners on anti-glare coatings.
Every 3 monthsVacuum or brush dust from the ventilation slots and check that cables are fully seated and not pulling on the ports.
Every 6 monthsCheck the manufacturer's support site for firmware updates, especially if you see compatibility issues with new computers or docks.

Troubleshooting

Most display problems trace back to cables, input selection or computer settings. Work through these checks before contacting support; for model-specific messages, consult the manufacturer's manual.

ProblemPossible causeWhat to try
"No signal" messageWrong input selected; loose cable; computer asleep or outputting to another screen.Select the correct input in the OSD, reseat both cable ends, wake the computer, and press Win+P (Windows) or check Displays settings (macOS).
Text looks blurry or the picture does not fill the screenComputer not sending the native resolution; scaling or overscan settings.Set the resolution to 3440 × 1440 and adjust OS scaling instead; turn off overscan or "aspect" options in the OSD.
Flicker, dropouts or black screen at high refresh ratesCable not rated for the bandwidth; adapter or dock limitation.Use a certified DisplayPort or Ultra/Premium High Speed HDMI cable, connect directly without adapters, or lower the refresh rate to test.
Colors look washed out over HDMILimited RGB range sent by the computer or console.Set the output to full RGB range in the graphics driver, or match the monitor's HDMI range setting.
Monitor does not wake from sleepDeep-sleep option on the input; graphics driver issue.Press a monitor button or reselect the input; disable deep sleep / auto-input in the OSD; update the graphics driver.
Laptop not charging over USB-CLaptop needs more power than the port supplies; cable not rated for charging; USB-C port on laptop is data-only.Check that the laptop accepts USB-C charging and needs no more than 90 W; use the supplied or a 5 A certified cable; try another USB-C port on the laptop.
No sound from the speakersComputer outputting audio elsewhere; monitor volume muted.Select the monitor as the audio output device and raise the monitor's volume in the OSD.

Energy use and running costs

The LG 35BN75C has a total energy consumption (TEC) rating of 100 kWh per year. ENERGY STAR's TEC method assumes the screen is on about 35% of the time (roughly 8.4 hours a day) and asleep the rest. At $0.17 per kWh, it costs about $16.99 per year.

Estimated from 32.4 W on and 0.09 W sleep at $0.17/kWh, 365 days a year.
Daily useEnergy per yearCost per year
4 hours on, 20 asleep48 kWh$8.16
8 hours on, 16 asleep95.3 kWh$16.19
12 hours on, 12 asleep142 kWh$24.22

On-mode power is measured at the factory-default brightness. Turning brightness up or charging a laptop through USB-C increases consumption; using short sleep timers reduces it.

Frequently asked questions

What size and resolution is the LG 35BN75C?

It has a 35 in. screen with a native resolution of 3440 × 1440 (UWQHD ultrawide), giving a pixel density of about 107 ppi.

How much power does the LG 35BN75C use?

It draws 32.4 W when on and 0.09 W in sleep. Its ENERGY STAR TEC rating is about 100 kWh a year, or $16.99 at $0.17/kWh.

Can the LG 35BN75C charge a laptop over USB-C?

Yes. It has a USB-C port with Power Delivery rated at up to 90 W, so a compatible laptop can charge, send video and use the monitor's USB ports over one cable.

What inputs does the LG 35BN75C have?

The ENERGY STAR record lists HDMI, DisplayPort, and USB. Port counts and versions (for example HDMI 2.1 or DisplayPort 1.4) are not included in the certification data; check the manufacturer's specifications.

What panel type does the LG 35BN75C use?

It uses an IPS LCD panel with a rated maximum luminance of 250 cd/m². IPS-type panels offer wide viewing angles and consistent color.

Sources and disclaimer

Specifications on this page come from the ENERGY STAR certified monitors dataset published by the U.S. Environmental Protection Agency (record certified March 14, 2022), retrieved October 7, 2026.

The setup, operating, maintenance and troubleshooting guidance is written by ManualHarbor's editors for this specific product type and configuration. It is an independent guide — not a reproduction of the manufacturer's manual — and ManualHarbor is not affiliated with LG. Always follow the safety instructions, installation requirements and warranty terms supplied with your unit, and contact LG or an authorized service provider for warranty repairs and replacement parts.

Running-cost figures use assumed U.S. average utility prices and are estimates for comparison only. See our editorial methodology for details.