[SOLVED] Legacy and uefi and windows 10

[ameramdouni420]

Hi, i really need to understand this so i recently was switching between win7 and win 10 and always when i want to install win 10 it tell me i should convert to gpt,and when i want install win7 it tell me i should to convert to mbr and always use third party software to do that so i dont lose my data but last time when i was go to install win10 it didnt tell to convert to gpt, why? But i did anyway and it start to ask me to convert to mbr so i did little reaearch and switched to uefi only boot mode(it was uefi and legacy) my questions are
1. Does legacy mode works only with mbr?
2. Does win 10 install only at gpt(i dont think so since i could install it to mbr)
I wanna know how this things work and ist bad that i used uefi only

 

[Colif]

1. Yes
2 it prefers GPT but if you only have a legacy bios, it will use MBR. I have had both formats on same ssd and same PC

UEFI is a standard for modern bios, it was created by a consortium of hardware and software makers in 2006 (ish) designed to fix a lot of the short comings of legacy bios. Almost every modern motherboard has a UEFI bios now.

Legacy was created over 20 years ago and though it suited the machines of the past, it had limitations that would be a pain in coming years. For instance, MBR (Master Boot Record) format only supports drives up to 2.2tb in size and only allows 4 partitions max on a drive. Legacy bios doesn't know what a mouse is.

UEFI (Unified Extensible Firmware Interface) supports MBR and GPT. GPT (Guid Partition Table) (Guid = Global Unique ID (every drive on earth has its own ID number)) supports drives up to size of 18.8 million TB and lets you have as many as 256 partitions on a single drive.
UEFI introduced graphical interfaces to BIOS so it looks much better, and it knows what a mouse if used for.

UEFI is a perfectly fine choice if you don't want to use Win 7 32bit, (Win 7 64bit supports it)

 

[youkkef]

1. Yes
2 it prefers GPT but if you only have a legacy bios, it will use MBR. I have had both formats on same ssd and same PC

UEFI is a standard for modern bios, it was created by a consortium of hardware and software makers in 2006 (ish) designed to fix a lot of the short comings of legacy bios. Almost every modern motherboard has a UEFI bios now.

Legacy was created over 20 years ago and though it suited the machines of the past, it had limitations that would be a pain in coming years. For instance, MBR (Master Boot Record) format only supports drives up to 2.2tb in size and only allows 4 partitions max on a drive. Legacy bios doesn't know what a mouse is.

UEFI (Unified Extensible Firmware Interface) supports MBR and GPT. GPT (Guid Partition Table) (Guid = Global Unique ID (every drive on earth has its own ID number)) supports drives up to size of 18.8 million TB and lets you have as many as 256 partitions on a single drive.
UEFI introduced graphical interfaces to BIOS so it looks much better, and it knows what a mouse if used for.

UEFI is a perfectly fine choice if you don't want to use Win 7 32bit, (Win 7 64bit supports it)

yea i understand that and thx for explaining it, what i don't understand is, first i have gigabyte uefi dual bios motherboard, and for the boot it was set to "legacy and uefi" from what i know windows can use only one of theme to boot, so if it was using legacy i wouldn't be able to install from gpt wich i did many time, and if it was set to uefi wich supporth both gpt and mbr why it would ask me to convert

 

[Colif]

Sorry, didn't know how much you didn't understand

The choice which has both UEFI & Legacy is a boot method, not how it formats drives. It offers a choice like that so that you shouldn't need to change bios when you first install an os, it can do either. If win 10 finds this setting, it will ask for GPT. If Win 7 finds it, it goes with MBR (though win 7 64bit does support GPT)

UEFI boot method supports both Formats to boot off, not to install as. It installs as GPT.
Since it followed Legacy, it has backwards compatibility so that PC that dual boot Win 10 & 7 can still run without having to mess with bios settings each time you want to boot 7.

Legacy can only boot MBR, and will format drives as MBR because of this. If Win 10 finds bios set as this, it will install as MBR.

Did you do anything different on the last install?
What process did you use? Did you upgrade win 7 to 10 the last time or are you clean installing?

If you upgrade win 7 to 10, then it won't require you to change the boot method (or convert to gpt)

Another possibility is, my Asus Z97 Board is also set to UEFI/Legacy, the 1st time I clean installed win 10, I had no idea about MBR/GPT and was unprepared for the GPT error myself, I had figured I could just do what I had always done, delete C and start again, to find that wouldn't work. So I deleted all the partitions and still it wouldn't work.
So I turned off the PC and tried again a little later, and this time it let me install.. as MBR. I assume what it did was swap the boot method it was using on the next startup

2nd time I clean installed win 10 I knew how it worked and wiped all partitions, and clicked next and it has installed as GPT.


Gigabyte Dual BIOS - Did you know its really just 1 BIOS + 1 backup bios that is never used, its entire job is to replace the main one if it gets corrupted. Not related, just thought I mention it.

this might be 4th draft by time i click answer...