Is your PC restarting out of nowhere while gaming, watching videos, or even just idling? You’re not alone. Random reboots can be caused by a mix of hardware, software, and power issues. Here’s how to fix them step-by-step.
⚠️ Common Symptoms of a Restart Problem
- PC shuts down and reboots without warning
- Restarts after a few minutes of gaming or heavy use
- No error messages or blue screen
- May happen repeatedly or randomly
These usually point to power, overheating, or driver issues.
🔧 Fix #1: Check for Overheating
- Use HWMonitor or CoreTemp to check CPU/GPU temps
- Clean dust from fans, heatsinks, and case filters
- Replace thermal paste if CPU temps go above 90°C
Overheating is a very common reason for unexpected restarts.
👉 Need to reapply paste? See our What Is Thermal Paste? How It Works & When to Replace It
🚧 Fix #2: Test Your Power Supply
- Make sure your PSU is high quality and the right wattage
- Use tools like OCCT or HWInfo to test voltages under load
- Try another PSU if available
Cheap PSUs often cause restarts when under stress.
👉 If it’s time for a replacement, see our Best Reliable Budget PSUs for Gaming PCs
🔓 Fix #3: Disable Automatic Restart
- Go to Control Panel > System > Advanced > Startup & Recovery
- Uncheck “Automatically restart”
This lets you see any error codes or blue screens instead of silent restarts.
⚖️ Fix #4: Run Windows Memory Diagnostic
- Type mdsched.exe in Start menu
- Restart and scan for RAM issues
- Replace faulty RAM if detected
Faulty or mismatched RAM can cause reboot loops.
👉 Need a replacement kit? See our Best DDR4 RAM for Gaming & Budget Builds
🪤 Fix #5: Update Drivers & BIOS
- Use Windows Update for core drivers
- Download latest GPU drivers (NVIDIA/AMD)
- Visit your motherboard site for BIOS update
Outdated or corrupt drivers often trigger random restarts.
🧰 Fix #6: Scan for Malware or Corrupted System Files
- Run a full antivirus/malware scan
Open Command Prompt as admin and run:
- sfc /scannow
- DISM /Online /Cleanup-Image /RestoreHealth
🛠️ Fix #7: Check for Faulty Peripherals or Devices
- Unplug all non-essential USB devices
- Try running with just keyboard/mouse
- Remove add-on cards temporarily (Wi-Fi, capture cards, etc.)
❓ FAQ
Does this only happen during gaming, or can it happen at idle too?
Both, and the timing is actually a useful diagnostic clue: restarts specifically under load point toward power or heat; restarts at idle are more often driver, malware, or Windows update related.
I ran Memory Diagnostic and it found nothing — does that rule out RAM?
Mostly, but not entirely — Windows Memory Diagnostic catches most hard failures but can miss RAM that’s unstable only at specific speeds/timings. MemTest86 (run from a bootable USB) is a more thorough second check if problems persist.
How do I know if it’s the PSU and not something else?
The clearest signal is restarts that correlate with load spikes — GPU-intensive game moments, multi-core CPU tasks — rather than random timing. If swapping in a known-good PSU stops the restarts, that confirms it.
🌟 Final Tips
- Make changes one at a time so you know what fixed it
- Log when the restart happens (after gaming? on idle?)
- If it continues, consider a clean Windows reinstall or hardware test
🔗 Related Reading
- Why Your PC Won’t Turn On: 7 Common Causes and How to Fix Them
- How to Fix a PC That Turns On but No Display
- How to Fix a PC That Randomly Turns Off While Gaming
As an Amazon Associate, PC Wizard Hub earns from qualifying purchases made through the links above.
⚠️
