Windows Failed OC and Win fails to boot

I tried to OC my system this morning, and now Windows isn't booting.
I have a GA-P55M-UD2 motherboard (BIOS ver F11) and an i5-750 CPU.

The only settings I changed was to disable the turbo boost then set the BCLK to 160 (to take the CPU to 3.2GHz).

After saving and rebooting, Windows failed to boot.
It got to the black Win 7 splash screen (with the glowing Windows logo) then it restarted.

As I had backed up my settings before the OC, I restored these settings and restarted.
However, Windows still failed to boot same as before.

Safe mode also failed to boot, and when I go into the system repair options it fails to recognise any installed operating systems to I can't system restore or anything else.

I guess I have to re-install Windows now, but does anyone have any suggestions for what I might have done wrong or things to check before I do this?

I was also wondering what I should set the SATA controller mode to? I have a Samsung Spinpoint F3 SATA drive.
I'm pretty sure it was set to ACHI mode before I changed anything, but when going into the standard CMOS settings screen my HD and DVD drive (both are SATA drives) show up.
They only show up when the SATA controller is set to IDE.
I assume this is normal?

Thanks for any advice!

 

Set EVERYTHING back to default in your BIOS. Try the drive in another PC if you have access to one.

Next time, overclock in little steps of 10 on the baseclock, Don't just ramp it up the whatever the hell you want! Thats a great way to wreck a CPU/mobo.

 

Did you try taking out the Cmos battery?

 

Yep, taking out the CMOS will get rid of the overclock and hopefully it'll boot as it was before the overclock.

 

Taking out the battery is one way of reseting it, but you shouldn't have to do that.

Most boards these days come with a Bios reset button on them, or atleast a jumper that you can use to reset the Bios with.

But reseting the Bios as mentioned is the answer when an overclock goes bad.

Edit: I missed the part about your drive settings. Leave it on IDE mate. You should only have to change that to ACHI if you are running an SSD driver.

 

If you take out the battery I recommend leaving it out for a few minutes. The jumper method is usually easier though. Also remember that when overclocking, you'll need to up the voltage aswell as the BCLK.

Finally, if you are unsure of any setting in the BIOS, leave it alone as it can mess things up badly - you can always ask the great members of this forum for their advice as I have done many a time.