INC-2026-04-04: Razer Blade 18 High Fan Noise & Elevated Temperature

Incident Summary

Field Value

Detected

2026-04-04 ~18:50 PDT (user report - sudden fan noise)

Mitigated

2026-04-04 ~19:15 PDT (killed runaway waybar process)

Resolved

2026-04-04 ~19:44 PDT (CSS fixes applied, waybar stable at 0% CPU)

Duration

~54 minutes (detection to resolution)

Severity

P3 (Medium) - System functional but thermally stressed

Impact

CPU at 86°C, fans at max RPM, CPU throttled to 800 MHz

Root Cause

Waybar CSS box-shadow declarations and infinite animations caused GTK3 software rendering loop at 50-96% CPU

Timeline

Time (PDT) Event

~18:50

User noticed sudden high fan noise after plugging in AC power

18:51

Initial diagnostics: CPU at 86°C, GPU at 54°C idle (7W, 0% util). GPU ruled out.

18:52

Process analysis: waybar PID 2140 at 96.1% CPU identified as heat source

18:53

Killed waybar, temps began dropping (86°C → 79°C)

18:54

Restarted waybar — returned to 52% CPU immediately. Not a one-off.

19:00

CSS animations commented out (glow-pulse, text-flicker, subtle-breathe). Still 53% CPU.

19:02

All remaining animations disabled. Still 52% CPU. Animations not sole cause.

19:10

Minimal config test (clock only): 0.0% CPU. Confirmed modules are fine.

19:15

Full modules + minimal CSS: 0.0% CPU. Confirmed CSS is the root cause.

19:25

Removed media module — still 57%. playerctl -F ruled out.

19:29

Disabled transition: all properties — still 58%. Not transitions alone.

19:32

Disabled box-shadow via sed — introduced CSS parse errors (unclosed comments)

19:40

Read full style.css, identified all corrupted lines. Properly removed multi-line box-shadow blocks, stray */ fragments, and last active animation (border-glow-cycle)

19:44

Waybar stable at 0.0% CPU. No CSS parse errors. Temps: 56°C and dropping.

19:46

Final thermal reading: CPU 56°C, ACPI 54°C. 30°C drop from peak. Incident resolved.

Symptoms

  • Sudden onset of high fan noise when AC power plugged in

  • CPU package temperature at 86°C during light desktop use (terminal, browser)

  • CPU throttled to 800 MHz (min frequency) — still couldn’t cool down

  • GPU completely idle (54°C, 7W, 0% utilization) — not the cause

  • System uptime was 1 day 20 hours at time of incident

Impact Assessment

Systems Affected

System Status Impact Duration

modestus-razer

Resolved

~54 minutes

User comfort

Restored

Fan noise eliminated

Business Impact

  • Users affected: 1 (personal workstation)

  • Data loss: No

  • Hardware risk: Sustained 86°C for unknown duration (possibly hours before detection)

  • Workaround: Killing waybar provided immediate relief

Metadata

Field Value

Incident ID

INC-2026-04-04-001

Author

Evan Rosado

Created

2026-04-04

Last Updated

2026-04-04

Status

Resolved

Post-Incident Review

2026-04-04 (same session)