PC Overheating — Causes and What to Do

Overheating is one of the leading causes of sudden shutdowns, performance throttling, and long-term hardware damage. Here’s how to identify and handle it.

Signs Your PC Is Overheating

  • Sudden shutdowns or restarts with no warning
  • Fan running at full speed constantly (very loud)
  • PC is slow — especially during games or heavy tasks
  • Hot air coming from vents, or chassis hot to touch
  • Blue screen errors (BSOD) that happen randomly

How to Check Your Temperatures

Using HWMonitor (Free)

  1. Download HWMonitor from cpuid.com
  2. Install and open it
  3. Look for these readings under your CPU:
    • Idle temp (nothing running): should be 35–50°C
    • Under load (during gaming or heavy use): should be below 85°C
  4. GPU temps under load should also stay below 85–90°C

Danger zones:

  • CPU above 90°C under load — overheating
  • CPU above 100°C — throttling or shutting down to protect itself

Common Causes

1. Dust Buildup (Most Common)

Dust blocks vents and fans, trapping heat inside. Laptops can get severely clogged in 1–2 years. Desktops in 2–3 years depending on environment.

2. Dried Thermal Paste

The thermal paste between your CPU and heatsink dries out over 3–5 years. When it dries, it stops conducting heat properly.

3. Broken or Stuck Fan

If a fan stops spinning, temperatures spike immediately. You can often hear the difference — one fan missing from the normal sound.

4. Poor Ventilation

Laptop on a bed or pillow blocking all vents. Desktop in a tight enclosed cabinet. Both prevent hot air from escaping.

What You Can Do at Home

For desktops:

  • Blow out dust with compressed air through the vents (do this outside)
  • Make sure all case fans are spinning
  • Keep the case in an open, ventilated area

For laptops:

  • Use on a hard flat surface — never on a bed or lap
  • Elevate the back slightly using a book for better airflow
  • Use a laptop cooling pad if you use it intensively

When to Bring It In

You need professional service if:

  • Temperatures are over 90°C at idle or light use
  • The fan is making grinding or rattling noises
  • Thermal paste hasn’t been replaced in 4+ years
  • The laptop runs hot immediately even after cleaning vents
  • PC is shutting down or throttling during normal tasks

We clean dust, replace thermal paste, and service fans. Most laptops show a dramatic improvement after a proper thermal service.

Submit a service request →