We have all felt that cold spike of anxiety. You press the power button, the fans whir to life... and then nothing. A black screen. A cryptic beep code. Or worse, the dreaded Blue Screen of Death (BSOD) scrolling cryptic error codes before it reboots.

Go to support.hp.com . Step 2: Enter your product serial number (found on a sticker on the bottom of a laptop or the back of a desktop tower). Step 3: Navigate to the "Software and Drivers" tab. Step 4: Filter by "Diagnostic Tools." Step 5: Download HP PC Hardware Diagnostics UEFI .

Before you rush to buy a new motherboard or pay for an expensive repair, there is a free, powerful set of tools already waiting inside your HP computer. The secret lies in the suite.