It turned out that some USB devices cause that. It's a long story but HP failed horribly and destroyed my laptop and I had to replace it.
Hopefully you can unplug some USB thing and it will boot up.
About a month ago I bought an HP Envy 14, and was pretty happy with it, after a couple of weeks I've been having a small problem. Most of the time when I turn on my laptop or just get it out of sleep mode and log in, it will blink a couple of times (turn to black screen then back to normal) and then go back to normal. This has been going on for a bit to get me ticked off, I can still use the mouse but I can't use my top buttons (Brightness up/down, Volume up/down, etc.) until the blinking has stopped. I don't know what's wrong, I've updated all my drivers especially the display adapters. If you guys have some sort of idea of what the problem is that would be helpful. Thank you.
Specs if you need to know:
Windows 7 Home Premium (64-Bit)
Intel Core i5 M 460 @ 2.53 GHz
6 GB RAM
Display Adapters: ATI Mobility Radeon HD 5650 & Intel HD Graphics