Windows wont start when using sata III

I have an Asus P8z77-v LK mobo using a OCZ vertex 4 128gb SSD. Everything worked fine until today when i try to start my computer it gets stuck on the starting windows screen. so i make sure everything is plugged in and restart and go in to the bios and my SSD and Disk drive arent being recognized. so i mess with it a bit and try using my ssd on sata II and it gets recognized and boots instantly. i did a CMOS reset and now they're being recognized using sata III again but it still wont go past the starting windows screen, the screen doesnt freeze or anything. it just doesnt continue to boot up

Is the BIOS set for AHCI or SATA mode? If the setting in the BIOS doesn't match what it was when Windows was installed on the drive, it will do as you have described.

It has always been set to AHCI, i never changed it. The drive worked perfect for 2 months then recently started doing this. I switched it to IDE to test it real quick but it just BSOD'd so i switched it back.

Can you boot from another disk and then run diagnostics on this drive?

HD tune pro shows it working fine.

That's got me stumped...

You and me both.

Might you have changed the physical port into which you plugged the SSD? On my Asus board, I couldn't boot until I figured out that each drive had to be plugged into the SAME sata port as it was the last time the bios was happy.

I found this out by deduction, running Win 7 repair and then all would be ok. Windows was finding the boot disk and "connecting" it to the sata port the bios thought it was in.

Madeline