AMI Hi-Flex BIOS

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The Hi-Flex BIOS POST screen

AMI Hi-Flex BIOS, also called "AMI Color BIOS" by enthusiasts (due to it's colourful setup utility), is a version of AMIBIOS released by American Megatrends. Compared to AMI Plus BIOS (which it replaced), it introduced an entirely new setup utility, a longer BIOS string format (which was used with slight changes for all newer versions of AMIBIOS and all versions of Aptio until 2020), and more setup options.

AMIDIAG, which a limited version of was included with some versions of AMI Plus BIOS, was completely removed from the BIOS ROM with this version. Although some of AMIDIAG's features remained in the new setup utility.

Setup Utility

The new setup utility introduced different menus for related settings, giving more space to store them. It also introduced 16 new colour schemes that can be toggled with F2/F3 keys on keyboard. The colour schemes look like the following:

Technical limitations

Like AMI Plus BIOS, hard drives of up to 32 GB in capacity can be configured in the setup utility. However, due to lack of LBA (Logical Block Addressing) on most versions, only up to 504 MB can be used. Although, some late versions of Hi-Flex had LBA in the Advanced CMOS Setup menu through code forks or modifications. Additionally, various workarounds do exist for this limitation, such as using Ontrack Disk Manager.

New identification string format

As mentioned, Hi-Flex BIOS has introduced the string format that was in use for all newer versions of AMIBIOS and all versions Aptio until 2020 (when the string was finally removed), with only some slight changes over time.

C: Processor architecture, R: ROM size, MMMM: Manufacturer/OEM identification code, FFFFFFFF: BIOS feature identification (often 00101111), SSSSSS: BIOS compile date OR subcore release date, DDDDDDDD: BIOS identifier, Project: BIOS project ID (no maximum characters), K: Keyboard controller (KBC) ID

CR-VVVV-00MMMM-FFFFFFFF-SSSSSS-DDDDDDDD-Project-K

Note: The project ID section is only present on later cores of AMIBIOS 6 and later releases. The keyboard controller ID is also not used on AMIBIOS 07.00.xx, AMIBIOS 8 and Aptio.

Example string: 61-1108-001169-00101111-071595-440BX/ZX-1440B000-H

This string is for a 11.08 revision ("1108") 128 KB ("1") size AMIBIOS 6 ("071595", main subcore for it) for a motherboard for 686 architecture processors ("6") with Intel 440BX or 440ZX chipset ("440BX/ZX") and an AMIKEY-2 clone keyboard controller ("H") made by MSI ("1169").

For a list of codes for each field, click here.

Intel fork

Main page: List of BIOS and UEFI firmwares used by Intel motherboards

Intel has forked AMI Hi-Flex BIOS subcore 111192 and used it on most of their motherboards manufactured from 1993 to 1997. Early versions of this fork are not much different from the original AMI version, while later versions look quite different.