Is it possible to install Windows 7 on a Windows 8 computer?

StrykerChaos said:

Well I am going to try one more time and change the bios because I had the boot set to both UEFI and GSM and it says it needs to be GSM. So before I go and try to install windows 7 what is the proper way to create the hard drive? should I shrink the drive "I already did this" and do you have any other advice as far as getting the UEFI to show up.

If you set the BIOS CSM, you will need to reinstall Windows 8.

Use UEFI OS or UEFI/ CSM OS.

Or change it back to UEFI or Dual.



Ray why is it suggested here to enable CSM in Downgrade Windows 8 to Windows 7 if one is wanting to install in UEFI mode?

   Note

You may also need to

Make sure CSM is ENABLED, & set to UEFI boot.

enable Boot Menu.

enable BIOS password.

Technical Note: UEFI BIOS vs. Legacy BIOS - YouTube

Isn't CSM the same as Legacy BIOS but sometimes offering a Dual Mode? If so could Win7 be installed in Legacy mode alongside Win8 in UEFI in Dual Mode? Has this been tried?

gregrocker said:

Or change it back to UEFI or Dual.



Ray why is it suggested here to enable CSM in Downgrade Windows 8 to Windows 7 if one is wanting to install in UEFI mode?

   Note

You may also need to

Make sure CSM is ENABLED, & set to UEFI boot.

enable Boot Menu.

enable BIOS password.

Technical Note: UEFI BIOS vs. Legacy BIOS - YouTube

Isn't CSM the same as Legacy BIOS but sometimes offering a Dual Mode? If so could Win7 be installed in Legacy mode alongside Win8 in UEFI in Dual Mode? Has this been tried?

Some BIOS's are set to UEFI or Legacy, or UEFI/Legacy when Secure Boot is DISABLED, some same to be Pre-set to boot Windows 8 only.
My test PC is Pre-set to UEFI/Legacy.

when I restart the computer it says no bookable OS until I change the boot options back to default.

gregrocer said:

Isn't CSM the same as Legacy BIOS but sometimes offering a Dual Mode? If so could Windows 7 be installed in Legacy mode alongside Win8 in UEFI in Dual Mode? Has this been tried?

You would need two HDD's & use One Time Boot Menu to boot each OS.

can I avoid all of this hasel by deleting everything off the hdd and installing windows 7 then installing windows 8, or will I still have the same issue?

But why should CSM - which is Legacy Mode - be enabled at all on a UEFI install, especially in a Dual Boot with pre-installed Win8?

StrykerChaos said:

can I avoid all of this hasel by deleting everything off the hdd and installing windows 7 then installing windows 8, or will I still have the same issue?

You shouldn't need to, unless you give up on UEFI mode and want to install in Legacy Mode a normal BIOS install to MBR disk. Bypass UEFI to Install WIn7

I've been able to install Win7 in a Dual Boot with pre-installed Win8 by only disabling Secure Boot - although I had probs formatting the stick which are recounted in the link i provided.

Did you change anything else besides Secure Boot in BIOS? If so try changing it back to allow a UEFI install. Legacy Mode or CSM is to get around installing in UEFI mode.

theog said:

gregrocer said:

Isn't CSM the same as Legacy BIOS but sometimes offering a Dual Mode? If so could Windows 7 be installed in Legacy mode alongside Win8 in UEFI in Dual Mode? Has this been tried?

You would need two HDD's & use One Time Boot Menu to boot each OS.

But why should CSM - which is Legacy Mode - be enabled at all on a UEFI install, especially in a Dual Boot with pre-installed Win8?

gregrocker said:

But why should CSM - which is Legacy Mode - be enabled at all on a UEFI install, especially in a Dual Boot with pre-installed Win8?

CSM is the controller, to set 16bit BIOS or 64bit UEFI.

I disabled fast boot and disabled secure boot. The OS mode selection is set to CSM and UEFI OS, should it be UEFI and not both?