For your model. Without that I can't check to see if a service manual is out or what the blinks tell us.
Waiting for your updates.
PC envy 17 TouchSmart won't boot-blank screen, capslock 3 blinks; power button and F12 on solid
HP Envy 17 Touchsmart will not boot. Power On key lights up along with F12 key and Caps Lock key blinks on and off. Fan runs for about 3 seconds and stops. After about 20 seconds lights go off and the cycle repeats. Have tried replacing motherboards (2) with no change in symptoms. Hard disk runs but no video on screen. Have tried using external HDMI monitor with no changes in symptoms. Removed DVD drive and ram with no changes. Have cloned 1TB harddisk and tried a different harddisk with no changes. Used a different power supply same result. Removed battery and tried holding Power On button several times as described on HP support page with no change in symptoms.