On pressing power button lights blinking unlimited times , not on lapt

If your HP ProBook 640 G1 blinks its power/Wi-Fi/speaker/charging LEDs continuously but won’t turn on, and you’ve already tried:

• Removing RAM & SSD
• Holding the power button (discharge)
• Flashing BIOS via USB

…then this sounds like a hardware-level failure. Let’s break this down properly so you can confirm what's going wrong:

HP laptops use LED blink codes to show hardware issues.

1. Count the number of blinks (power LED or caps lock/wifi light often blinks a pattern: e.g., 3 blinks, pause, 3 blinks).
2. This pattern tells you which component is failing:
3. of Blinks Error Meaning 1 blink CPU failure 2 blinks BIOS corruption 3 blinks Memory/RAM error 4 blinks Graphics controller 5 blinks System board (general) 6 blinks BIOS authentication

❗If it's blinking non-stop without a pause, that's often motherboard failure or short circuit (no specific code = severe issue).

• Try powering on with battery removed, AC adapter only.
• Try a different adapter if possible. A faulty adapter can cause this behavior.

Do this on a non-metal surface:

• Remove battery
• Remove SSD/HDD
• Remove RAM sticks (both)
• Disconnect CMOS battery (if possible, for 2+ minutes)
• Hold power button 60 seconds
• Plug in only power adapter
• Power on

🟡 With no RAM installed, the laptop should blink 3 times to show “RAM missing.”
→ If it does not do that → motherboard or CPU failure is likely.

If BIOS is corrupted, the laptop may not post, but you can attempt BIOS recovery from USB:

1. Go to HP’s site → Support page for 640 G1
2. Download the BIOS .exe file → extract it on another working Windows PC
3. Copy BIN or ROM file to a USB drive formatted in FAT32
4. Plug it into the laptop's USB port
5. Press and hold Win + B or Win + V, then press power button
6. Keep holding the keys for ~30 sec

🟢 If BIOS recovery is supported, the laptop may beep and read the USB → flash new BIOS.

⚠️ Doesn’t work on all models. If no reaction, this confirms severe hardware-level problem.

Condition Likely Issue LED blinks in infinite loop Motherboard fault or BIOS corrupt beyond recovery No POST, no beeps, no fan Dead CPU / severe mobo failure No RAM = no 3 blinks Mobo not even initializing POST BIOS flash via USB fails BIOS chip failure / southbridge problem

• Replace motherboard (~$50–$100 used/refurb on eBay)
• If you're experienced, inspect board for burnt areas or swollen capacitors

• Sell for parts (RAM, screen, keyboard, etc. are still valuable)
• Consider replacement; this model is nearly a decade old (2013–2014)

If you want help finding a replacement motherboard or part number, just tell me your CPU (i5 or i7?) and I’ll get you a direct link.