AHCI Problem Aspire 5520 (Mod Bios v1.33)

[carlosalbertoar]

Hello everyone, I'm new in the forum. I do not know if I'm in the right place.

I updated the BIOS on my notebook Aspire 5520 to show the advanced options on Sata AHCI (v1.33 Mod), I enter the BIOS, I change IDE to AHCI, save and leave the Bios then displays a message "Phoenix AHCI Rom" ... Detects my Sandisk SSD Ultra Plus and says "AHCI successfully installed".
But the computer restarts and if I enter the bios to check, he returned alone mode for IDE.

My CMOS battery is not weak, and get no BIOS error message.

What may be happening ???

Thank you.