Windows dosent want to start

HEre is my problem, i did everything my manual told me to do, I checked all my connection, everything is plugeed in fine, i even got my pc working for about 1h30 and then decided to shut it down. Then i wanted to do something, i tried to power it on but i always end up with a blue screen and my windows vista 7 not wanting to start up. I tried to load the fail-safe setting in the bios of my mobo, but still nothing, tried optimized one, nothing again, i put everything as i did when i fist started my computer but still, nothing.

Specs:
I5 750
P55M UD2
Samsung spinpoint f3 500gb
A ide dvd drive
hd 5770
corsair 650tx psu.

Everything their is new, but still i can get nothing to work and that is really annoying and i dunno what to do now.

got it working was just a simple boot problem, re booted it and it worked now running at 3.6 ghz stable and my gpu at 960/1440 with xfx stock bios