Common PC Building Issues and Solutions
Last updated: August 2025
Power Issues
System Won't Turn On (No Lights, No Fans)
Symptoms
- No response when pressing power button
- No LED lights on motherboard
- No fan spinning
- Complete silence from system
Troubleshooting Steps
- Check PSU power switch: Ensure switched to "I" (ON) position
- Verify wall outlet: Test outlet with another device
- PSU cable connection: Ensure PSU cable firmly connected to wall and PSU
- Front panel connectors: Verify power button connected to correct pins
- 24-pin ATX connector: Ensure fully seated and clicked in place
- 8-pin CPU power: Check top-left motherboard connector
Advanced Diagnostics
PSU Paperclip Test: 1. Disconnect all PSU cables from components 2. Short green wire to any black wire on 24-pin connector 3. PSU fan should spin if PSU functional 4. If PSU works but system doesn't, motherboard issue likely
Minimal Configuration Test: - Remove all components except CPU, one RAM stick, PSU - Remove GPU, use integrated graphics if available - Disconnect all drives and peripherals - Try to POST with minimal setup
System Powers On But Immediately Shuts Off
Symptoms
- Fans spin for 1-3 seconds then stop
- System cycles on/off repeatedly
- May see brief LED activity
Common Causes
- CPU overheating: Cooler not properly mounted
- PSU insufficient: Not enough wattage for components
- RAM issues: Incompatible or faulty memory
- Short circuit: Metal touching motherboard inappropriately
- CPU power: 8-pin connector not connected
Solutions
- Check CPU cooler mounting: Ensure even pressure, thermal paste applied
- Verify PSU wattage: Calculate total system power draw
- Test single RAM stick: Try different slots, different modules
- Remove standoff shorts: Check no extra standoffs under motherboard
- Disconnect non-essential: Remove all except basic components
Random System Shutdowns During Use
Symptoms
- System shuts down without warning during operation
- May occur under load or idle
- Restarts automatically or requires manual power on
Troubleshooting
- Temperature monitoring: Check CPU/GPU temperatures with HWiNFO64
- PSU stress test: Run Prime95 + FurMark simultaneously
- Event Viewer: Check Windows logs for shutdown causes
- RAM testing: Run Windows Memory Diagnostic or MemTest86
- Power settings: Disable fast startup, check power plan settings
Display Issues
No Display Output
Symptoms
- Monitor shows "No Signal" message
- Black screen but system appears to run
- Monitor stays in standby mode
Step-by-Step Diagnosis
- Monitor connection: Ensure cable connected to GPU, not motherboard
- Monitor power: Verify monitor powered on and functional
- Cable testing: Try different cable (HDMI, DisplayPort)
- Input selection: Check monitor input source selection
- GPU seating: Reseat graphics card in PCIe slot
- GPU power: Verify all PCIe power connectors attached
Advanced Solutions
Integrated Graphics Test: - Remove dedicated GPU - Connect monitor to motherboard output - If display works, GPU or GPU power issue
CMOS Clear: 1. Power off system completely 2. Remove CMOS battery for 5 minutes 3. Or use CMOS clear jumper per motherboard manual 4. Reinstall battery, power on
RAM Reseating: - Remove all RAM modules - Clean contacts with isopropyl alcohol - Install one stick in different slots - Test each module individually
Display Artifacts or Corruption
Symptoms
- Strange colors, lines, or patterns on screen
- Flickering or unstable image
- Partial display corruption
Causes and Solutions
- GPU overheating: Check GPU temperatures, clean fans
- VRAM issues: Run GPU memory test (VRAM test in FurMark)
- Driver corruption: Uninstall GPU drivers with DDU, reinstall latest
- Cable issues: Try different display cable
- Monitor issues: Test with different monitor
- Overclocking: Reset GPU to stock speeds
Boot and BIOS Issues
System POSTs But Won't Boot to Windows
Symptoms
- BIOS/UEFI screens appear normally
- Gets stuck at Windows loading screen
- Boot device not found errors
Solutions
- Boot device priority: Set correct drive as first boot device
- SATA cable check: Ensure storage drive connections secure
- Boot mode: Verify UEFI vs Legacy boot mode matches installation
- Secure Boot: Disable if causing compatibility issues
- Windows repair: Boot from Windows installation media, try repair
Stuck in BIOS Loop
Symptoms
- System boots to BIOS every time
- Can't exit BIOS to normal boot
- BIOS settings don't save
Troubleshooting
- CMOS battery: Replace motherboard battery (CR2032)
- Load defaults: Reset BIOS to factory defaults
- Boot device detection: Ensure storage drives detected in BIOS
- Fast Boot: Disable fast boot options
- CSM settings: Enable/disable Compatibility Support Module
BIOS Won't Load/Black Screen
Symptoms
- No BIOS splash screen
- Can't enter BIOS setup
- System appears dead but fans spin
Solutions
- Clear CMOS: Reset BIOS settings to defaults
- CPU compatibility: Verify CPU supported by motherboard
- BIOS version: May need BIOS update for CPU compatibility
- Minimal hardware: Remove all except CPU, RAM, PSU
- Motherboard inspection: Check for damaged components
Memory Issues
System Doesn't Detect All Installed RAM
Symptoms
- BIOS shows less RAM than physically installed
- Windows reports incorrect memory amount
- Only some modules detected
Diagnosis Steps
- Module compatibility: Check motherboard QVL (Qualified Vendor List)
- Slot population: Use correct slots for dual channel (usually 2,4)
- Individual testing: Test each module separately
- Slot testing: Try working modules in different slots
- Clean contacts: Remove modules, clean with isopropyl alcohol
Blue Screen Errors Related to Memory
Common BSOD Codes
- MEMORY_MANAGEMENT
- IRQL_NOT_LESS_OR_EQUAL
- PAGE_FAULT_IN_NONPAGED_AREA
- SYSTEM_SERVICE_EXCEPTION
Solutions
- Memory testing: Run Windows Memory Diagnostic (mdsched.exe)
- Extended testing: Boot MemTest86, run for 8+ hours
- XMP/DOCP disable: Turn off memory overclocking
- Voltage adjustment: Slightly increase DRAM voltage (1.35V → 1.4V)
- Single module: Test system stability with one RAM stick
Slow Performance Despite Adequate RAM
Symptoms
- System sluggish despite sufficient RAM capacity
- Applications take long to load
- Frequent hard drive activity
Checks
- Memory speed: Verify RAM running at rated speeds (XMP enabled)
- Dual channel: Ensure modules installed in correct slots
- Background apps: Check Task Manager for memory usage
- Virtual memory: Verify page file settings appropriate
- Driver issues: Update chipset and memory controller drivers
Storage Issues
SSD/HDD Not Detected
Symptoms
- Drive doesn't appear in BIOS
- Drive not visible in Windows Disk Management
- System can't find boot device
Troubleshooting
- Cable connections: Check both SATA data and power cables
- Different cables: Try different SATA data cable
- Different ports: Try different motherboard SATA ports
- Power supply: Verify sufficient PSU SATA power connectors
- Drive testing: Test drive in different computer
M.2 NVMe SSD Issues
Common Problems
- Drive not detected in BIOS
- Slower than expected performance
- System won't boot from M.2 drive
Solutions
- Slot compatibility: Verify M.2 slot supports NVMe (not just SATA)
- PCIe lane conflicts: Check if M.2 slot shares lanes with other slots
- BIOS settings: Enable NVMe support, check boot priority
- Thermal throttling: Ensure M.2 SSD has adequate cooling
- Firmware update: Check for SSD firmware updates
Slow Storage Performance
Symptoms
- Longer than expected boot times
- Slow file transfers
- Applications load slowly
Performance Checks
- Benchmark testing: Use CrystalDiskMark or AS SSD Benchmark
- SATA mode: Ensure SATA mode set to AHCI (not IDE)
- Drive health: Check S.M.A.R.T. data with CrystalDiskInfo
- Free space: Maintain 15-20% free space on SSDs
- TRIM status: Verify TRIM enabled for SSDs
Cooling and Temperature Issues
High CPU Temperatures
Dangerous Temperature Ranges
- Intel: >85°C concerning, >100°C critical
- AMD: >85°C concerning, >95°C critical
- Thermal throttling: Performance reduces to prevent damage
Solutions
- Cooler mounting: Check CPU cooler properly mounted with even pressure
- Thermal paste: Reapply if old, dried, or improperly applied
- Case airflow: Ensure adequate intake and exhaust fans
- Dust cleaning: Clean CPU cooler fins and case fans
- Cooler adequacy: Verify cooler rated for CPU TDP
High GPU Temperatures
Temperature Guidelines
- RTX 5060/5060 Ti: <80°C good, >90°C concerning
- RTX 5070/5070 Ti: <85°C good, >95°C concerning
- RTX 5080/5090: <87°C good, >95°C concerning
Cooling Solutions
- Fan curves: Adjust GPU fan curves for more aggressive cooling
- Case ventilation: Improve case airflow, especially GPU intake
- Undervolting: Reduce GPU voltage while maintaining performance
- Dust removal: Clean GPU fans and heatsink
- Thermal pads: Replace thermal pads if very old GPU
System Overheating
Symptoms
- Multiple components running hot
- Frequent thermal throttling
- System instability under load
Comprehensive Solutions
- Case fan configuration: Set up proper intake/exhaust airflow
- Positive pressure: More intake than exhaust reduces dust
- Cable management: Improve airflow by routing cables properly
- Component spacing: Ensure adequate clearance around hot components
- Ambient temperature: Consider room temperature and case location
Performance Issues
Lower Than Expected Gaming Performance
Symptoms
- FPS lower than benchmarks suggest
- Stuttering or frame drops
- Performance worse than similar builds
Diagnostic Steps
- GPU driver update: Install latest graphics drivers
- Background processes: Close unnecessary applications
- Windows updates: Ensure Windows fully updated
- Power settings: Set Windows power plan to "High Performance"
- Game settings: Verify appropriate quality settings for hardware
Advanced Optimization
- RAM speed verification: Ensure XMP/DOCP enabled for rated speeds
- GPU boost clocks: Monitor actual vs advertised boost clocks
- CPU utilization: Check for CPU bottlenecks in CPU-heavy games
- Storage performance: Ensure games installed on fast storage
- Thermal throttling: Monitor temperatures during gaming
System Feels Slow Despite Good Specifications
Common Causes
- HDD as boot drive: Upgrade to SSD for significant improvement
- Insufficient RAM: 16GB minimum for modern systems
- Background software: Bloatware or resource-heavy applications
- Windows indexing: Search indexing using CPU resources
- Malware: Run full system scan with Windows Defender
Hardware Compatibility Issues
Components Not Working Together
Symptoms
- System works with some components but not others
- Instability when all components installed
- Performance lower than individual component capabilities
Compatibility Checks
- CPU/Motherboard: Verify socket and chipset compatibility
- RAM compatibility: Check motherboard QVL for memory
- PSU adequacy: Ensure sufficient wattage and connectors
- Physical clearance: Check component sizes fit in case
- PCIe slot availability: Verify adequate expansion slots
New Component Causes Issues
Troubleshooting New Installs
- Driver installation: Install appropriate drivers for new component
- BIOS update: May need motherboard BIOS update for compatibility
- Power requirements: Verify PSU can handle additional power draw
- Conflict resolution: Check for resource conflicts with existing hardware
- Incremental testing: Install one component at a time
Getting Help
When to Seek Professional Help
- Multiple troubleshooting attempts fail
- Potential hardware damage suspected
- Warranty concerns about self-repair
- Lack confidence in performing procedures
- System needs specialized tools or expertise
Preparing for Tech Support
- Document symptoms: Write down exact error messages
- List recent changes: Note any new hardware or software
- Component list: Prepare full system specifications
- Testing results: Record what troubleshooting already attempted
- Warranty information: Gather purchase receipts and warranty terms
Online Resources
- Manufacturer websites: Official troubleshooting guides
- Community forums: Reddit r/buildapc, Tom's Hardware
- Video guides: YouTube channels for visual troubleshooting
- Official support: Manufacturer chat/phone support
Prevention Tips
Building Best Practices
- Read all manuals before starting
- Work in well-lit, static-free environment
- Take photos during disassembly for reference
- Keep components in anti-static bags until installation
- Test components before final assembly
Maintenance Schedule
- Monthly: Check temperatures, clean dust filters
- Quarterly: Clean internal components with compressed air
- Annually: Replace thermal paste, check connections
- As needed: Update drivers, monitor component health
This troubleshooting guide covers the most common issues encountered when building and maintaining PCs in the Indian market. When in doubt, consult component manuals and manufacturer support resources.