Background: When I installed Win10 on my new computer last year, I decided to use GPT partition scheme because I thought it was needed for something i would use, but now I can't remember why I made that decision. Otherwise, I would have installed Windows on MBR partition in a heartbeat (for ease of maintenance, cloning, imaging), but after a long thought I decided to go for GPT. And no, @acer-5100 , I don't intend to use native vhdx for serious work, because 1. I don't want another overlay between me and my hardware, and 2. I feel sorry for my SSDs and would like to spare them from write amplification. So I thought to make a list of all the things (parts of Windows operating system) that depend on GPT partition scheme or won't work without it. Maybe someone else will find it useful. Please add anything you know of. For starters, I write this from memory and it might be wrong, but here goes (I will edit it later if possible): - Bitlocker - Virtualization - Virtualization based security - HyperV - Windows Subsystem for Linux - Hardware Accelerated Graphics Scheduling - Resizable bar - Windows setup on drives with native 4k sectors - Format drives larger than 2.2 TB - Allow UEFI boot - Create more than 4 primary partitions on a single drive I'm sure there are more, but these are the ones I can think of right now. I know there were others that depended on Secure Boot, and Secure Boot in turn depends on GPT partitioning (?), so it's kinda indirect dependency. GL
People needs to complicate their life for no reason People sometimes is really masochist. I think secure boot (which is a big annoyance for any serious user) is the only thing for what GPT is needed. The cancer VBS works works on MBR (and I spent days to get rid of it w/o breaking Hyper-V) WSL works in MBR w/o any problem (both 1 & 2) Hyper-V obviously works HAG (never dealt with it, but given GPU-P works w/o problems I assume it works as well).
OK, regardless of the motives (goal), can we please just list all the components that depend on GPT/Secure Boot? GL
Freedom depends on it, freedom to mod your OS to your liking. If I wanted a cage instead of an OS I had a Apple device in my hands. That said I don't have any list, assuming there is one, just because I couldn't care less. Everything I need (which is a long list) works perfectly on MBR, and for testing purposes or in exceptional cases all I have to do is to initialize a vhdx as GUID, and use it either in hyper-v, vmware or natively.
Secure boot is worthless. I disable it in the BIOS. If you want a MBR disk, most any third party partition software will convert the disk with NO data loss. I use MiniTool Partition Wizard.
Oups, I remembered the reason why I needed to format GPT: Windows setup insisted because my drive had 4k sectors native (I converted it just before that). But, previously, I had successfully converted GPT to MBR partition scheme with some partition tool (AOMEI or Paragon or similar), it took a short time and Windows 10 ended up on a MBR partition but still thought it was on a GPT partition (verified with msinfo32.exe). But this was on a 512e drive, I need to try that on a 4k drive. And for that I will need to organize (find enough space for) a serious backup. I see @billmcct wrote about the same while I was writing this. Regardless, I still think it would be usefull to populate the first post with anything we can, for completeness. I added this to the first post. GL
Never happened to me, perhaps practically any drive sold in the last decade has 4K sectors (they are fully supported since Vista SP1 or so). Whatever one more reason to forget about setup and learn to deploy.
You need GPT to format drives above 3TB and aldo to allow UEFI boot. Also, MBR only allows for 4 or so primary partitions to be made. With GPT you can make unlimited primary partitions.
For now a problem next to nonexistent given most people has a main, relatively small, SSD for the OS, and big HDDs for data. This may change in the foreseable future when big SSDs become the norm, albeit HDDs are still the way to go for archival purposes. That was a problem in the Win9x days, but since NT you can boot the OS from a logical partition w/o any drawback, the problem is definitely solved with native vhds which become a thing BEFORE the GUID partitioning scheme
The size limit is 2 binary TeraBytes, if you don't do any advanced sector black magic. That's the maximum MBR usually can address. 4Kn drives are not really ready for the consumer sector, yet, they are used in Enterprises and Datacenters. The 512e translation is irrelevant for any consumer activity, provided the partitions are correctly aligned (which is practically guaranteed if you don't use a tool decades old).
In my case GPT is good for nothing! CSM=disabled, which forces GPT disks, is required for AMDs ResizeBar to work, but I have found no benefit from using that, so F it. Otherwise, all the "benefits" of using GPT are things I don't use or care about (many, HUGE partitions) and using CSM=disabled (full UEFI) is nothing but trouble. Causes all manner of problems, like Windows installer, Macrium rescue disks, etc. stuck in 800x600, requires 4 friggin' mostly empty, wasted space, partitions just for Windows on a "C" drive, sandwiched into them so you can't resize it no less. I can't remember everything at the moment, but every time I've tried to "get with the times" and run full UEFI and GPT disks, it resulted in things broken or working badly. Just a total annoyance for nothing and gimmicky features that don't improve anything and is really just a way for M$ to snag more control over YOUR hardware via TPM and "secure/safe" boot garbage. If UEFI boots any faster than BIOS, it's by imperceptible miliseconds and I don't GAFF (give a flying...). If it's somehow more redundant and bulletproof to corruption, I've NEVER had a MBR disk "corrupt itself" and I have backup images anyway, so I still don't GAFF.
Yes and no. It depends on the bios implementation and / or disk. The problem is bootability, not the GPT partition itself Say the mythical samsung 950 pro (and few other) had the bios extension just like any PCI/PCIe HDD SCSI/Raid/ATA controller, that would boot from even 20 years old machines. But given such drives are now rare (and pricey if bought used) the solution is either to mod the bios (if possible) or use Clover or Duet that can boot a system from NVME starting from BIOS machines and old buggy UEFI implementations.
I've installed windows on a couple of cheap Silicon Power and Inland Premium NVME SSDs with no trouble. Both were Gen3x4. The only "problem" was Windows itself wanting to put boot files on other drives in the system, requiring me to physically remove them before installing, but that's nothing to do with the type of drive, it's just M$ being M$.