Screen and Keyboard Test

Screen test: goes full screen. Click or press Space / arrow keys to change colour. Esc to exit.

• White, red, green, blue: look for black or coloured dots (dead or stuck pixels).
• Black: dim the room lights, look for glowing edges or corners (backlight bleed).
• Grey: look for faint ghost shapes (image retention from the store demo loop) and patchy areas.
• Gradient: should be smooth with no visible stripes.

Measuring refresh rate…