Why are my RGB lights stuck on rainbow?

Rainbow is what most RGB gear does when nothing is telling it otherwise. So when your lights are stuck on it, something between your RGB app and the hardware isn't getting through. Here's why, and the fixes in the order most likely to work.

Checked November 5, 2026. Every fact links to its source at the bottom of the page.

Why rainbow is the default

Kingston memory ships with a default rainbow wave, and a G.Skill tech says its memory stays on rainbow unless its software is running.
Corsair gear shows its saved hardware lighting until iCUE starts.
Fan and LED hubs run their own built-in modes at power on, until they're linked to the motherboard. One hub's manual says it starts in its 7 color mode.
Animated looks are sent live by your app, and some devices go back to their built-in effects the moment the app stops.

Fixes, most likely first

Your RGB app isn't running. Check it started with Windows, and restart it. Its background service can hang too: Corsair has a Restart iCUE Service button in iCUE's settings, and ASUS users fix stuck Aura lighting by restarting the Aura lighting service.
A hub is in its own mode. Many cases have an LED button that switches the hub to motherboard sync. MSI says to hold the LED switch for 3 seconds, and on a Lian Li Lancool II Mesh you press the M button 7 times.
A hub is missing power or USB. Some hubs need SATA power and a direct USB connection. Lian Li says to connect SATA power and plug USB straight into the motherboard, not a splitter.
Two apps are fighting. Only one RGB program can reliably control a device. Uninstall the ones you don't use, and turn off Windows Dynamic Lighting, which can also compete for your lights.
It broke after an update. A Windows 11 update once left G.Skill memory stuck on rainbow, and HP fixed Omen memory stuck on rainbow with a BIOS update. Update your BIOS and your RGB app.

Turn the lights off when the PC is off

If your lights glow rainbow while the PC is asleep or shut down, that's your motherboard, not your app. On ASUS boards, set Advanced, Onboard Devices Configuration, LED lighting to all off for sleep and soft off. Gigabyte has a matching setting for LEDs in sleep and soft off, and some MSI boards have an EZ LED Switch that turns off the board's lights and its RGB headers.

The easy fix: RGB Engine

RGB Engine is built to keep your lights on your look. It starts with Windows, takes your lights back after the PC wakes from sleep, and restarts its hardware connection by itself if your lights stop answering. One app runs every brand in the case, so there's nothing left to fight over.

Get RGB Engine at launch

Questions

Why do my RGB fans go back to rainbow after restarting?

Your RGB app hasn't started yet, or didn't start at all. Until it does, fans, hubs and memory show their built-in default, which is usually rainbow. Make sure the app starts with Windows.

Why does my RGB go to rainbow after sleep?

Some RGB apps don't take the lights back when the PC wakes, so the hardware falls back to its default. RGB Engine takes your lights back on its own after every wake.

Why are only some of my lights stuck on rainbow?

Those parts usually sit on a hub that's in its own mode, or belong to a brand your app doesn't control. Switch the hub to motherboard sync with its LED button, or let RGB Engine control every brand from one app.

How do I stop RGB glowing when my PC is off?

Turn it off in your BIOS. ASUS and Gigabyte boards have settings for LEDs in sleep and soft off, and some MSI boards have an EZ LED Switch.

Sources

Gaming memory support, Kingston (default rainbow wave).
RGB pattern without the G.Skill app running, G.Skill forum.
How to set up hardware lighting in iCUE, Corsair.
What to do if iCUE can't detect your RGB memory, Corsair (Restart iCUE Service).
PWM and ARGB hub V2.0, GameMax.
Common modes, OpenRGB.
Switching the case hub to Mystic Light sync, MSI.
Lancool II Mesh RGB FAQ, Lian Li.
Product FAQ, Lian Li (hub power and USB).
Aura defaults on wake from sleep, ROG forum.
Conflicting programs, SignalRGB.
Control Dynamic Lighting devices in Windows, Microsoft.
Windows 11 22H2 and G.Skill Trident Z Neo RGB, Microsoft Tech Community.
Omen HyperX lighting stuck on wave rainbow, HP Support Community.
Turn off RGB when the PC is off, SignalRGB (ASUS and Gigabyte BIOS settings).
EZ LED Switch, MSI.

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