[Guide] AMI (non-UEFI) BIOS Modding

[fo18]

Hello,
I have old board ASUS P5G41T-M LX3 with Xeon E5450. When i install nvme with adapter and clover boot, nvme not detect with clover.
I try to install nvme on another board with clover boot:

• Gigabyte GA-H61M-DS2 -> nvme detect
• Gigabyte GA-78LMT-S2P -> nvme detect
• Varro G41V-R3 -> nvme detect

On bios Varro G41V-R3 in Storage Configuration Menu AHCI RAID option exist, otherwise in ASUS P5G41T-M LX3 AHCI RAID missing

Storage Varro G41 AHCI

82801GB ICH7/R REV. A1 P5G41T-M LX3 VS VARRO G41V-R3

Varro G41V-R3 Device

Is possible to add AHCI/RAID option on ASUS P5G41T-M LX3? or insert SATA AHCI and RAID Controllers to Option ROMs? which module?
I can't find sata raid on extracted bios Varro G41V-R3 PCI Option ROM With MMTool 3.22 BKMOD, 3.26.

Thank's

Edit by Fernando: Text re-formatted to save space and for better readability

P5G41T-M-LX3-ASUS-0503-XEON.rar (526 KB)

VARRO G41V-R3 G4177L0D.rar (404 KB)