HP envy 17 TouchSmart won't boot-blank screen, capslock 3 blinks; power button and F12 on solid

[bighank]

Went through HP suggestions to remove battery and hold power on button for 30 seconds.

Replaced battery and no change. The power on button is lit along with the F12 button and the caps lock button blinks 3 times. The fan comes on for about 3 seconds and then quits. This cycle repeats with fan cycling on and off. Hard Disk does not seem to run at all. The system is a HP envy 17 TouchSmart with 8GB ram and a 1TB Hard Disk.

Removed ram and used a pencil eraser to clean contacts then tried replacing ram in different slots, one 4GB stick at a time and both sticks. No change. Tried removing ram and re powering on. No change.

What do I do next? What is causing the no boot and blinking capslock?

 

[hang-the-9]

https/h30434.www3.hp.com/t5/Notebook-Boot-and-Lockup/laptop-envy-4-capslock-light-flashing-display-blank/td-p/3725748

 

[bighank]

Re: PC envy 17 TouchSmart won't boot-blank screen, capslock 3 blinks; power button and F12 on solid
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‎Laptop Model is: M7-j120dx HP ENVY TouchSmart 17 Notebook PC
Rev 1965-110

Disassembled case and replaced motherboard with exact same board
720265-501 6050A2549501-MB-A02

Reassambled and powered on with battery and with AC power adapter.
Get exactly same results with lights on and blinking as described above.

Tried removing RAM, cables to left side USB ports and electronic circuitry, removed DVD drive and Hard Disk,cloned Hard Disk with Acronis and tried cloned 1 TB SATA drive, NO CHANGE.

What do I try next? Thiught it was a bad MB but new MB has exactly the same symptoms as the original MB.

 

[hang-the-9]

If you have the RAM removed, does the system beep? Unless you got a bad motherboard or the CPU or something else is bad, most likely issue would have been the motherboard.