Problem with downgrade to Win7x64Pro on GPT disc

[marrier]

At the earliest sorry for my bad english, I'm from Czech.

I want to downgrade my ASUS X55A to Windows7 x64 Pro, but during install come the error:

I used this tuto: http://www.sevenforums.com/tutorial...e-firmware-interface-install-windows-7-a.html
I used Rufus to prepare bootable USB (but compared to tutorial is my version 1.3.4.270, and there is not GPT Partititon Scheme in Partition Scheme Option. So I used MBR Partition Scheme for UEFI computers).
I want install in UEFI mode, not in BIOS Mode.
Secure Boot is disabled. Fast Boot is disabled.

I read about bdcedit function on command line, I can run it, but I cannot work with it. Just this:

Thank you for all answers.

 

[theog]

Is this a OEM manufacturer's PC with Pre-installed Windows 8?

1) Downgrade to Windows 7.
Downgrade Windows 8 to Windows 7
Warning you must have the UEFI/BIOS firmware setting in Step Three set.

Make sure you read the NOTE at Step three.

2) If Using a USB Pen drive on a PC with a UEFI BIOS.
USB Pen drive need to be formatted to FAT32 as in
UEFI Bootable USB Flash Drive - Create in Windows
Take note of Step 11 for Windows 7.
Also you will need to use a USB 2.0 port, as there are no USB 3.0 drivers in Windows 7.


You will need to buy Windows 7.

 

[marrier]

Uuuuf. All was right, just CSM wasn't enabled. Now is install done. Thank you for all. Have a nice days.

 

[jimbo45]

Uuuuf. All was right, just CSM wasn't enabled. Now is install done. Thank you for all. Have a nice days.

Hi there.

Glad you got your problem solved - but just curious :

What's CSM. Another poster recently said the same thing about enabling CSM -- so if this is a decent solution what's CSM. I asked the same question to that poster but never did get an answer back.

Cheers
jimbo

 

[theog]

What's CSM. Another poster recently said the same thing about enabling CSM -- so if this is a decent solution what's CSM. I asked the same question to that poster but never did get an answer back.

Nice small video here:

For more info on uEFI:
Windows and GPT FAQ
Unified Extensible Firmware Interface - Wikipedia, the free encyclopedia
UEFI Firmware
Technical Note: UEFI BIOS vs. Legacy BIOS, Advantech(EN) - YouTube
Sample: Configure UEFI/GPT-Based Hard Drive Partitions by Using Windows PE and DiskPart

CSM = Compatibility Support Module

http://en.wikipedia.org/wiki/Unified_Extensible_Firmware_Interface

CSM booting

For backwards compatibility, most of the UEFI implementations on PC-class machines also support booting in legacy BIOS mode from MBR-partitioned disks, through the Compatibility Support Module (CSM) which provides legacy BIOS compatibility. In that scenario, booting is performed in the same way as on legacy BIOS-based systems, by ignoring the partition table and relying on the content of a boot sector.[28]

BIOS booting from MBR-partitioned disks is commonly called BIOS-MBR, regardless of it being performed on UEFI or legacy BIOS-based systems. As a side note, booting legacy BIOS-based systems from GPT disks is also possible, and it is commonly called BIOS-GPT.

Despite the fact MBR partition tables are required to be fully supported within the UEFI specification,[33] some UEFI firmwares immediately switch to the BIOS-based CSM booting depending on the type of boot disk's partition table, thus preventing UEFI booting to be performed from EFI System partitions on MBR-partitioned disks.[28] Such a scheme is commonly called UEFI-MBR.

 

[marrier]

I thought CSM will install just in BIOS mode, but it's not that.

 

[theog]

ASUS are pre-set to UEFI & Legacy mode.