Install Win7 w/Legacy Oprom enabled for installation - then disable?

Hi
I have a brand new Dell Inspiron 15 7548 series that I want to quad boot with 8.1 (as main OS; will be using the OEM OS it came with) , 7 Ultimate, 10 Tech preview and Fedora 21. Because I can

I have figured out that i CAN install windows 7 in UEFI / GPT mode, but the "legacy Oprom" needs to be enabled in the BIOS. This is fine and my 8.1 still boots, but instead of just showing the Dell logo and the spinny circle, it shows the dell logo, then hangs a couple seconds, then shows the blue windows logo and boots up. Everything still works, this is just a minor annoyance.

What i'm wondering is, can I have the legacy oprom enabled for installation of Windows 7, and then proceed to turn it off and Win7 will still boot?

Cheers

Doubful. I have been able to dual boot Win7 with WIn8 on about half the installs tried. It requires the settings in BIOS setup for CSM or Legacy BIOS tested in all settings choices, any other UEFI/EFI settings to be set correctly, Secure Boot disabled.

If Windows 8 will boot with these settings which for that BIOS are required to install Win7, then the multi Boot will install. If not it may require reinstalling Windows 8.

You can report back all BIOS settings choices mentioned plus any others you see for UEFI/EFI, CSM, Legacy BIOS, etc. Pictures can help.

Ok, thanks. Guess i'll just have to try it and see

Update - the Windows 7 installer wouldn't run on my laptop, kept pushing for a CD/DVD driver, even though I was installing from an USB (Usb 2.0 port) and my laptop has no dvd drive (?) (this was with legacy oprom on, installer wouldn't boot if it wasn't)

SO, I used KYHI's awesome WinPE environment which has WinNT installer in it to install instead, and it even gave me the option to inject my drivers into it, which I did happily, and everything booted nicely. This was with my laptop set to full UEFI mode. No legacy oprom. So it seems you only need the legacy oprom for the install procedure, if using the setup.exe as your means of install. Since I used a Win8.1 UEFI PE environment with WinNT installer v3.5 in it, it booted fine under full UEFI.

Maltesespace said:

Update - the Windows 7 installer wouldn't run on my laptop, kept pushing for a CD/DVD driver, even though I was installing from an USB (Usb 2.0 port) and my laptop has no dvd drive (?) (this was with legacy oprom on, installer wouldn't boot if it wasn't)

That error almost always means a bad installer, rarely has proved to be an actual driver needed.

Maltesespace said:

SO, I used KYHI's awesome WinPE environment which has WinNT installer in it to install instead, and it even gave me the option to inject my drivers into it, which I did happily, and everything booted nicely. This was with my laptop set to full UEFI mode. No legacy oprom. So it seems you only need the legacy oprom for the install procedure, if using the setup.exe as your means of install. Since I used a Win8.1 UEFI PE environment with WinNT installer v3.5 in it, it booted fine under full UEFI.

I don't know what this is. Can you please explain it fully so others understand what KYHI is and exactly how it helped you install to UEFI without Legacy OpROM.

When Windows 8 already exists in most cases it doesn't require CSM or Legacy modes at all.

gregrocker said:

That error almost always means a bad installer, rarely has proved to be an actual driver needed.

Nope. Tried multiple media, including a Win7 ultimate boxed dvd from M$, said boxed DVD on a USB drive, and Win7 Enterprise x64 on a USB drive. All had the same annoying issue.



I don't know what this is. Can you please explain it fully so others understand what KYHI is and exactly how it helped you install to UEFI without Legacy OpROM.

When Windows 8 already exists in most cases it doesn't require CSM or Legacy modes at all.[/QUOTE]

KYHI is a member of 7/8/10 forums who made an awesome WinPE environment. It is available to download from his signature IIRC. Once I burned his iso to an USB, also with the Win7 USB inserted, I booted to his PE, launched NT setup, (it even has customisation options!!) pointed it to the install.wim and let it run. Within 5 minutes, Win7 was imaged to that partition with my laptop's drivers to boot! Booted up and all was well.

It's possible that the driver error you got meant what it always does which is the bootable installer was not good, so that the WinPE merely provided a working bootable installer from which you could launch setup.

How does a WinPE merge drivers into the Win7 files used for install?