Bios mod needed for HP Pavilion 15BC406TX

Hello everyone
I am having HP laptop with i5-8300H processor. As usual BIOS lacks any meaningful settings. Yesterday I tried to install windows 7 on the same and was greeted with a BSOD that BIOS is not ACPI compliant. There is no option in bios to change the acpi settings. I have already enable legacy mode.
I have checked and found that Measured and Verified Boot is disabled(Screenshot Attached.) Please help me with a modded BIOS so that I can install windows 7 on this.

Thanks in advance


@sangalaviral - What ACPI needs to be set for Win7, do you know?

Was the original system Win10 on this? If yes, then ACPI is already set to one high enough for Win7, but something removed from ACPI table possibly, causing Wn7 to not be compatible.
And that would require some ACPI table editing which you’d have to ask about in the OS section of the forum where those guys that know would see your request easier and be able to offer more help if they can.

Please link to HP EXE BIOS download, I can’t find it

When I checked using acronis true imager, acpi is set to RAID. My system has 2 Drive. 1st is 2TB Samsung SSD and 2nd is M.2 240GB Kingston SSD. Windows 10 is installed on 2TB SSD and I am want to install Windows 7 on 240GB SSD. When check both are being shown as RAID.
Original OS was windows 10.
Here is the link to BIOS

@sangalaviral - ACPI doesn’t have a RAID setting, so whatever you see in Acronis isn’t ACPI setting related. However, if you are wanting to install different OS to different disks, then you need to go into BIOS and disable RAID and set AHCI
Since original system was Win10, they likely disabled (ie edited to remove) Win7 related/required stuff in the ACPI part of the BIOS, hopefully someone will be able to help you in your other thread.

I’ll drop your extracted BIOS there for them to inspect, and tag a few people here that I see modify ACPI tables
But, your BIOS download contains three different BIOS images, so before I can do that, you need to tell me which of these is your system ID, maybe you see when flashing BIOS, or maybe you can find somewhere in HWINFO64 >> ssid:084ED,084F8,084F7
If BIOS mod is required, you will need flash programmer (CH341A = SOIC8 test clip w/ cable), let me know if you need linked examples of these

Sounds like culprit may be DDB table, from this thread (Maybe yours)? BSOD 0xA5 - I looked in BIOS options for one of the larger BIOS and see only BDAT Table support (disabled)…ompliant.24875/

You may be able to disable ACPI to continue install, from what I see on the bottom of this Microsoft page…acpi-bios-error

First: I also encountered the same problem, click to view .
I have a few ideas to solve WIN7 0x000000A5 ACPI ERRORS. The first idea: use clover, clover is an indispensable tool for Hackintosh. clover can load external SSDT Acpi Table, maybe we can use clover to load SSDT Acpi Table compatible with WIN7, avoid WIN7 0x000000A5 ACPI ERRORS, without flashing the BIOS.
Second idea: I found here a possible solution to the WIN7 ACPI. This is the solution provided by the Microsoft community.
The third idea: (Click to view lenovo TianYi510S-07ICB BIOS picture )lenovo TianYi510S-07ICB PC BIOS version: M22KT34A install WIN7 0x000000A5 ACPI ERRORS, BIOS version M22KT41A release time: 2019/11/7, flash BIOS M22KT41A to lenovo TianYi510S-07ICB will not have WIN7 0x000000A5 ACPI ERRORS . You can use tools to analyze the differences between the two BIOSes of M22KT41A and M22KT34A and find the cause of the problem. I am newbie and I am learning the basics of BIOS modification. I can only provide ideas, not solutions.

Second: What command do I enter in CMD to see the content in this picture? Click to view picture
Third: Pure uefi mode installs WIN7, legacy bios mbr installs WIN7 I all see this interface , I can’t disable ACPI installation WIN7 by pressing F7 on this interface, click to start installation, I can’t press f7 continuously Disable acpi to install win7.Please tell me how to disable acpi to install win7?

Flash COREBOOT into the motherboard, use COREBOOT to boot WIN7, and avoid WIN7 0x000000A5 ACPI BSOD ERRORS.coreboot is a Free Software project aimed at replacing the proprietary BIOS (firmware) found in most computers. coreboot performs a little bit of hardware initialization and then executes additional boot logic, called a payload. With the separation of hardware initialization and later boot logic, coreboot can scale from specialized applications that run directly firmware, run operating systems in flash, load custom bootloaders, or implement firmware standards, like PC BIOS services or UEFI. This allows for systems to only include the features necessary in the target application, reducing the amount of code and flash space required.

1)Make sure you boot in UEFI mode with CSM enabled, not in pure UEFI without CSM.
2)Your Windows 7 installation media needs to have USB3 drivers integrated because windows 7 dont support usb3 naturally. (not even 2 that works from xhci chipset mod)(windows 7 support usb2 naturally from ehci mode)
3)You need a modified graphics driver to support Windows 7.
4)When you install win7 you will take this: The “processor does not support windows 7” and you need to patch here: -

It simply not worth the hassle.