Sata mode selection?

[Drake5]

I've just been taking a look in my BIOS for the first time and noticed a setting called 'sata mode selection'.

I have a Sata HDD but 'IDE' mode was selected so I changed it to 'AHCI' and my PC wouldn't boot until I changed it back to IDE.

Is this normal? Bit confused...

Cheers

 

[Drake5]

What's the difference between AHCI and IDE Mode?

Thanks

 

[Drake5]

Would it be worth reformatting in AHCI mode or shouldn't I bother?

Thanks