# Second Hand LED Monitor: buying guides

> Manufacturer specs for used monitors (ports, USB-C charging, stand, panel), cable and charging guides, and checks for dead pixels and backlight bleed.

## Backlight bleed and IPS glow explained

Source: https://secondhandledmonitor.com/guides/backlight-bleed/

How to tell normal glow from a panel worth returning.

### What it is

Backlight bleed is light leaking around the edges of an LCD panel, most visible on dark screens. IPS glow is a silvery sheen that changes with viewing angle. Some glow is normal for IPS; heavy bleed that doesn't change with angle is a defect.

### How to test

In a dim room, show a full black image at about 50% brightness. Look straight on from a normal distance, then move your head. Glow shifts as you move; bleed stays put.

- Test at your normal brightness, not 100%
- Compare the corners
- Check again after loosening the bezel screws slightly (on monitors where that's safe)

## How to check a used monitor for dead pixels

Source: https://secondhandledmonitor.com/guides/dead-pixels/

How to test for dead and stuck pixels, and what counts as a fault.

### Dead vs stuck pixels

A dead pixel stays black on every colour. A stuck pixel stays lit in one colour, usually red, green or blue. Stuck pixels can sometimes be revived with a pixel-flashing tool; dead pixels cannot.

### The test

Show full-screen solid colours (white, black, red, green, blue) and look closely at the panel from about 30cm. A browser-based dead-pixel test is enough.

- Clean the screen first so dust doesn't fool you
- Check the corners and edges
- Photograph anything suspicious for a return claim

### What's acceptable

Manufacturers' pixel policies vary. Many allow a few defects on new panels. For a used monitor, ask the seller to state the pixel condition in writing, and use eBay's returns if the item isn't as described.

## Monitor ports and cables: what you need

Source: https://secondhandledmonitor.com/guides/ports-and-cables/

HDMI, DisplayPort and USB-C versions needed for 4K and 144Hz.

### The short version

For 4K at 60Hz you need HDMI 2.0 or DisplayPort 1.2 or later. For 1440p at 144Hz and above, use DisplayPort. USB-C with DisplayPort Alt Mode can drive the screen and charge a laptop on monitors that support it.

### Used-specific gotchas

Used monitors are often sold without the original cable or power brick. Older HDMI cables may cap refresh rates. Budget for a certified cable if one isn't included.

- List the monitor's inputs before buying
- Check your graphics card's or laptop's outputs
- Confirm a power supply is included (many are external bricks)

## Used monitor buying checklist

Source: https://secondhandledmonitor.com/guides/used-monitor-checklist/

What to check in the listing and on arrival when buying a used monitor.

### Before you bid

Read the full listing. Find the exact model number and check its native resolution, refresh rate and inputs on the maker's spec page.

- Exact model number in the listing
- Photos of the screen switched on
- Stand, power supply and cable included?
- Seller feedback above 98%
- Returns accepted

### When it arrives

Test it within the return window. Run it at native resolution for at least an hour, because some faults only show once the panel warms up.

- Full-screen white, black, red, green and blue tests
- Every input port works
- No flicker at different brightness levels
- Buttons and on-screen menu respond