My Dell Alienware m15 R7 shows black screen on AC boot, as OS boots

Alienware laptop shows a black screen (backlight on) while system continues running (audio plays, fans active).

• More likely when powering on with AC adapter connected
• Less frequent when booting on battery first
• Occurs during normal use (e.g., video playback)

• Boot on battery
• Wait briefly
• Plug in AC after system stabilizes

This significantly reduces the issue.

• Updated drivers via Dell SupportAssist
• Reinstalled graphics drivers
• Ran hardware diagnostics (no issues)
• Disabled sleep / adjusted power settings
• Replaced battery

Issue started after heavy GPU usage with Topaz Video AI.

Has anyone encountered this behavior?

• Is this a known hybrid GPU / power-state issue?
• Did factory reset resolve it?
• Any permanent fix besides the workaround?