HP elitebook 840 G1 blinking lights, black screen

[Mindlery]

A friend sold this and asked me to wipe it.

There was no recovery so i decided to install win 10 64 bit as gpt. It booted to usb, i used diskpart to clean, convert to gpt at install screen. Proceeded with install.

When files were done copying, i force shut it down. I assumed on reboot the new owner would be greeted with "getting devices ready" etc

Because i was to do this quick i thought it was best option.

Less than an hour later the computer was brought back.

All it does is do a constant flash of power, wifi and volume over and over. Will not stop when holding power if plugged in. Also, getting 3 lights blinking by charger indicator front left at same rate. (3 lights every 2 seconds). But in between one white light flashes as well front left.

Took out ssd drive and it booted fine in my dell with efi boot. Like it owned the joint.

I did set hp bios to UEFI prior as i have done in other hp's and more. 

It was already on win 10 64.. but MBR. Still, this was not unusual to do. Secure boot was off and as far as i remember every security feature disabled. No passords in BIOS or win 10.

Currently have battery, cmos and ram disconnected. Will try after this... please, help is appreciated!

[Mindlery · Accepted solution]

Ok. Ptoblem solved.

I not only had to remove battery. MUST be battery, RAM and CMOS. You can the  hold power button (i did 2 minutes).

After, plug in CMOS and RAM. Leave battery out.

Plug in wall adapter, boot, then apply normal shutdown after successful boot. Put battery back in. Done.

[Mindlery]

*try to never interrupt OS install ever again*