New Install, Unsure About SSD Wipe and USing UEFI vs Legacy

iron7 · 08 Aug 2017

Installing 7 x64 (single boot) on a new XPS 13 with 10.

I successfully created a USB media that appears to launch fine in legacy mode, but is not detected in UEFI mode.

I was reading the clean install thread and didn't know if I should not go the legacy route for any reason.

Also, I have read recommendations for a zero'd out SSD before a new install, and was unsure if I should try to go that route first and any possible risks associated with it.

TIA

Lady Fitzgerald · 08 Aug 2017

iron7 said:

...Also, I have read recommendations for a zero'd out SSD before a new install, and was unsure if I should try to go that route first and any possible risks associated with it.

TIA

Do not zero out an SSD; that creates unnecessary writes on the SSD. If you need to remove all data from an SSD, use the Secure Erase feature in the support software for your SSD.

iron7 · 08 Aug 2017

Extra writes aside, and good reason to zero out on a brand new machine? It's an m.2 drive.

Lady Fitzgerald · 08 Aug 2017

iron7 said:

Extra writes aside, and good reason to zero out on a brand new machine? It's an m.2 drive.

It is not necessary to write 0s to an SSD to clear it.

iron7 · 09 Aug 2017

Is there a risk of harming the mbr? I would need a program to boot from usb as I intend to secure erase the system drive. Any recommendations for one to use?

Megahertz07 · 09 Aug 2017

Installing Win 7 on a M.2 drive on a new hardware isn't an easy task.
Fist thing you should do is an disk image of the current configuration (C: and D: ) so, if things go wrong, you can restore it.
Macrium Software | Your Image is Everything
Also do the recovery disk (read the manual).

I suggest you to install as UEFI - GPT.
UEFI (Unified Extensible Firmware Interface) - Install Windows 7 with - Windows 7 Help Forums
On BIOS, you must disable secure boot and fast boot.
Read my tutorial Create a Windows 7 USB flash installation with new drives for new MB's - Windows 7 Help Forums

Edit:
Windows7-USB-DVD- Installer doesn't create a UEFI boot able.
Use Rufus Rufus - Create bootable USB drives the easy way
UEFI Bootable USB Flash Drive - Create in Windows

iron7 · 10 Aug 2017

thanks mega.

Is there a risk of harming the mbr doing a secure erase? I would need a program to boot from usb as I intend to secure erase the system drive. Any recommendations for one to use?

AddRAM · 10 Aug 2017

There won't be a MBR if you secure erase the drive.

Why do you need to secure erase it, a simple format is all you have to do.

Or just use Diskpart and run the clean command.

The clean all command would write all zeros, but I wouldn't do that either, there is no reason to, especially with a ssd. Lady F explained why.

Disk - Clean and Clean All with Diskpart Command - Windows 7 Help Forums

Megahertz07 · 10 Aug 2017

There is two kind of BIOS. UEFI - GPT and Legacy - MBR
Your XPS is a UEFI - GPT system. There is no MBR on the disk.
When you begin the win 7 installation (a clean install) you delete all partitions and then create a new partition. But to Win 7 installation "see" the M.2 drive your installation disk must have the M.2 drivers.

If you don't do an image of your disks and make the Factory Recovery disk, you may end with a XPS without a OS (7 or 10)