PC Repair Guide: How To Diagnose PC Hardware Problems

Use the general diagnosis table below as a guide to finding the problem component. We have separate diagnostic pages for each component of the PC.

Symptom	Check Click on underlined items for further information
When I turn it on... It makes no sound and there are no lights	Check the Power Supply Check the Motherboard Check the CPU
When I turn it on... It just beeps	Read our Beep Codes List Check the Keyboard Check the Video Card Check the Memory Check the Motherboard
When I turn it on... It sounds normal but the screen is blank	Make sure the monitor has power Check the connection to the video card Check the Video Card
When I turn it on... It starts up but never loads the operating system	Check the Hard Disk Check the Memory Check the Motherboard Check the CPU
When I turn it on... It freezes BEFORE the operating system starts loading	Check the Keyboard Check the Video Card Check the Memory Check the Power Supply Check the Motherboard Check the CPU
When I turn it on... It freezes WHILE the operating system is loading	This is probably a software problem not covered in this hardware guide. If you are using Windows, try booting into safe mode by holding down the "F8" key or in some cases the "CONTROL" key.
While it is on... It makes a screeching or other loud noise	Check the Power Supply, CPU, Case or other Internal Fans Check the CD-ROM Check the Hard Disk Check the Floppy Drive
While it is on... It shuts itself off	Check the power features in the BIOS Check the power features in the Windows Control Panel Check the Power Supply Check that all fans are working Check for the accumulation of dust
If the problem occurs in association with a specific hardware component, visit the diagnostic page for that particular part.
Software Issues are not covered in this hardware guide.