Trying to reformat Samsung 850 1TB Windows 7 64 as UEFI/GPT

GlassDeviant · 23 Aug 2016

Every now and again I do a complete clean install of everything from my router firmware to my PC. I have never "reinstalled" on the SSD before though and it's been quite some time so I forget whatever I did when I first clean-installed it.

I was using this process:

Boot Windows 7 Update install disk (I upgraded from a Vista OEM disk ages ago).
Shift+F10 and run diskpart.
select disk 0
clean all
create partition primary align=1024
format fs=ntfs
assign
active
exit
exit

When I rebooted the installer would not let me proceed because the disk (I assume it meant BIOS) was set to EFI and it wanted a GPT partition. So I went back to diskpart and converted the disk to GPT and remade then reformatted the partition. The partition again could not be used because...it was GPT.

So I had to go into the BIOS and make it non-EFI (CSM/Legacy), which I did not want to do. Windows 7 is working "ok" now but how do I install from a pre-SP1 Windows 7 disk with UEFI enabled and using GPT partitions? Or can I just turn on UEFI and not worry about going to GPT?

samuria · 23 Aug 2016

You don't create partitions clean the drive boot Windows and let it create partitions and format

ThrashZone · 23 Aug 2016

Hi,
OS Type for win-7 should be set at Other OS not uefi in bios
Win-7 was never intended for a uefi install but you can if you insist :)
UEFI (Unified Extensible Firmware Interface) - Install Windows 7 with

Personally I would only have C and no system reserved partitions,
A folders structure is a lot better than a bunch of partitions that are never larger enough....

Megahertz07 · 23 Aug 2016

This is what I did to install Win 7 as UEFI / GPT
On BIOS:
- SATA=RAID or AHCI
- OS=Other
- Storage Boot and PCI device to UEFI only

- Boot your Win 7 installation on UEFI mode, go to install, custom, advanced, delete all partitions, create a new one (Win will create 3 partitions) and proceed.

GlassDeviant · 23 Aug 2016

I want to avoid the extra partitions, this is just wasted space. My previous install was one single partition, I just can't remember what the instructions I followed were to get it that way.

Megahertz07 · 23 Aug 2016

The 3 partitions created are the minimal.
- First is a 100M UEFI FAT 32 partition
- Second is a 120M raw MS reserved partition
- Third is the remaining space NTFS partition (drive C:)

ThrashZone · 23 Aug 2016

Hi,
mbr disk supports up to 4 partitions
There's no need to go gtp on a 1tb disk above 2tb is when you pretty much have to so windows sees the entire disk.

GlassDeviant · 24 Aug 2016

Guess I will stick with what I have then.

ThrashZone · 24 Aug 2016

Hi,
What is that ?
Post a screen shot of disk management.

Brds7t7 · 24 Aug 2016

GlassDeviant said:

Guess I will stick with what I have then.

With regards to UEFI/Secure Boot, as ThrashZone says, it isn't needed on Windows 7. It's designed for Windows 8 and above. Stick with Legacy BIOS for 7.

Also, if your disk is below 2TB then I would stick to MBR. You can convert a 2nd disk (e.g. Storage disk) that's above 2TB to GPT within Windows even when using Legacy BIOS. But, I would leave the boot disk as it is.

I have Samsung 850 EVO 250GB as boot drives in all my systems and I don't set any of them to GPT.