Computer hangs at boot but is fine when restarted.

Hello,

I built my computer about 2 weeks ago, all was fine until for the past week every time I restart or power on my pc it will hang at the BIOS screen until I restart it and then it will load fine. I have disabled full screen image in my BIOS so I can see what's going on but it seems to freeze before it gets to it, if that makes sense.. And as I said, when I hit the restart button it will load up fine. I am trying to update my BIOS at the moment but when it needs to restart this keeps happening and I am requested to run start up repair. No BSOD at all, no over clocking done yet, RAM is stock. Have tried booting with out USB's and certain HDD's. Also I have changed the SATA Cable going to my SSD. Someone mentioned voltage issues in another forum and possibly a way to increase the voltage for booting up??

This is a real problem at the moment as I am desperately trying to update my way out of date BIOS on my ASUS P8Z77 Deluxe.

MY specs atm:

Asus P8Z77 - V Deluxe
Intel Core i5-2500 3.30GHz
2 x Gigabyte GeForce GTX 560Ti
Corsair Vengeance Blue 16GB DDR3 1600 MHz
Corsair Professional Series 1050W Modular PSU
OCZ Agility 3 240GB 2.5" SSD

Thanks

JO