Dual boot Windows 10 home and windows 7

[rkattar]

Hi All,

I have an Asus ROG GL502VS laptop with Win 10 home edition installed on the SSD. I would like to install Windows 7 on the HDD to be able to play older win games. I already created a windows 7 to go usb disk, but it throws an error while booting from usb 3.0. Could someone please help in letting know the procedure to dual boot windows 10 and win 7 in asus rog laptops? Thanks

 

[BFG-9000]

If you can't drop the USB ports to 2.0 mode in the BIOS there's a workaround for installing Win 7 from USB 3.0. I suggest removing the SSD while you install 7.

Keep in mind your Skylake laptop is not on the official list of those supported in Win 7.

 

[rkattar]

If you can't drop the USB ports to 2.0 mode in the BIOS there's a workaround for installing Win 7 from USB 3.0. I suggest removing the SSD while you install 7.

Keep in mind your Skylake laptop is not on the official list of those supported in Win 7.

Hi BFG-9000. I did search on enabling usb 2.0 mode in BIOS, but not able to find that option anywhere. I also have only usb 3.0 ports. I was actually thinking of having a dual boot menu option. But by disconnecting the SSD and installing win 7 on the HDD, the dual boot menu option might not be visible later after connecting both. Can you please clarify on this?

 

[VJ_Gamer]

Disconnect the SSD. After Windows is installed on the HDD you want to be able to boot independently, then you can reconnect other SSD. Decide which drive you want to be your normal boot drive and make that the priority in UEFI. Then use the bcdboot command to add the secondary operating systems to the boot menu.

Good Luck. Peace.

 

[BFG-9000]

It's better to use the BIOS to select which drive to boot from (and is C:\) because then you could always format any single drive and would still be able to boot from the other. If you used a boot manager on one drive to boot either OS, neither OS will be available in case that drive dies. And it would be nearly impossible to simply repair the boot sector of the OS on the secondary drive because it'll think it's installed on drive D:\, which would no longer exist. So you'd actually need to reinstall both OSes. On your laptop I think you can invoke the BIOS' boot menu by pressing Esc on bootup instead of F2 (with Fast Boot option off), which is nearly as convenient as a boot manager.

Windows 7 is only supported for just over two more years as well (to Jan 2020) so consider flexibility for the near future. The workaround is intended for Intel NUCs, but slipstreaming the USB 3.0 xHCI driver into the install media would likely accomplish the same thing.

The reason you want to install Windows when only one drive is attached is it's kind of unpredictable which drive the installer will choose to put the boot partition and any recovery partitions on, which could both hose the other OS and make things unbootable if the other drive is ever removed or formatted.

 

[rkattar]

Disconnect the SSD. After Windows is installed on the HDD you want to be able to boot independently, then you can reconnect other SSD. Decide which drive you want to be your normal boot drive and make that the priority in UEFI. Then use the bcdboot command to add the secondary operating systems to the boot menu.

Good Luck. Peace.

Hi VJ_Gamer. I have a query. Windows 10 home is most likely installed on GPT partition type on the SSD. For installing Win 7 32 bit, would require a MBR partition type on the HDD. So by disconnecting the SSD, installing win 7 on HDD and later reconnecting and running bcdboot, would it be able to invoke the different partition types for win 10 and 7 correctly into a common boot menu?

 

[VJ_Gamer]

You can only boot from a GPT drive if you're using a UEFI-based computer running a 64-bit version of Windows. You can still covert from MBR to GPT.

1. Open command prompt and type in DISKPART and press Enter
2. Then type in list disk (Note down the number of the disk of windows 7)
3. Then type in select disk number of disk
4. Type in convert gpt.

Good Luck. Peace.

 

[Colif]

I see problems ahead

1. Your laptop has only got windows 10 drivers, nothing else. You can't use the win 10 drivers in Windows 7. If it had win 7 drivers, Asus would likely have a work around for USB 3.1 on their site, they nice like that.

2. Ideally if you setting up a dual boot system you install win 7 first and then win 10, only as how is win 10 going to know the win 7 install is there? the only way you will be able to boot off win 7 doing it this way is to change the bios boot method every time you want to boot

3. If win 7 were 64bit, you could use UEFI boot method

"While in UEFI mode, the Windows version must match the PC architecture. A 64-bit UEFI PC can only boot 64-bit versions of Windows. A 32-bit PC can only boot 32-bit versions of Windows. In some cases, while in legacy BIOS mode, you may be able to run 32-bit Windows on a 64-bit PC, assuming the manufacturer supports 32-bit legacy BIOS mode on the PC."

- https://answers.microsoft.com/en-us/windows/forum/windows_10-hardware/windows-10-32-bit-native-uefi-install-on/c72ff865-859a-43d7-b24c-5e726efba22a

3 doesn't necessarily mean it won't work, it just throws a curve ball at you. It might or it might not.

4. How big is hdd? converting it to MBR will mean ytou can only access 2tb of the drive, if its any bigger the extra will be unusable

 

[BFG-9000]

Intel 100-series chipsets have Windows 7 drivers right on WindowsUpdate. You know ASUS is using the USB 3.0 integrated into the chipset because that supports up to 8 ports so it would be silly to spend money on an external controller, plus then it wouldn't be bootable. The problem is USB 3.0 is too new for rudimentary xHCI drivers to be included on Win 7 install media unless you slipstream it in yourself.

The major problem I see is if your laptop is designed to use the power-saving Intel IGP normally, then switch to the GTX1070 for 3D applications. Windows 7 (unlike XP and Win 10) requires that all installed GPUs use the same driver so will only work properly if you can disable one of the GPUs.

The other issue is UEFI Secure Boot must be disabled for Win 7 to boot. I don't expect anyone to try a 32-bit OS on this as there aren't any drivers for the GTX1070, so UEFI itself and GPT are fine.

These problems are why I recommend setting up Windows 7 completely independent of the 10 disk--if it doesn't work, nothing on the 10 install is damaged or altered so you can just boot to 10 and format the HDD.

Skylake processors are only fully supported by Windows 7 until July 17, 2018. Kaby Lake is not supported at all, and if you dare to install 7 anyway (it works fine if you aren't using the GPU, with 100-series chipset), then WindowsUpdate will refuse to run (you could always manually install the monthly "Security Only Quality Update").

 

[rkattar]

Thank you for all the answers. Another option is that since I already have an existing windows 7 usb to go disk (windows 7 installed on the usb drive), is there any way that I would be able to boot the pen drive via usb 3.0? Currently when I am trying to boot windows 7 from usb 3.0, a Blue Screen of Death is triggered always after the boot logo. Any fix for this usb 3.0 booting problem? (I repeat, it is not about starting an new windows 7 installation by slip streaming 3.0 drivers, but rather booting the already installed windows 7 usb drive via usb 3.0)

 

[BFG-9000]

You can try cloning the USB stick to HDD, then it would not be booting from USB.

I wouldn't expect much though, unless the system the Windows To Go stick was made on was substantially the same as this laptop, as otherwise the new problem would be the correct SATA or AHCI drivers aren't already installed either. Unlike Win 9x, Win 7 cannot fall back to 16-bit MS-DOS compatibility mode until it installs the drivers! You can try installing them while the stick is booted on the old system but I expect it would be one problem after another--for example it may demand to be reactivated before you can login, before you have any working ethernet or Wifi drivers installed.