EFI stands for Extensible Firmware Interface, and is an updated version of BIOS. It sits between firmware and the operating system in the software stack.

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31
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How do I remove an EFI System partition from a drive in Windows 7?

I have an external HD which used to be my TimeMachine drive. I got a different drive for that, so I want the original drive back as an external on my Windows box, but it has this random 200 MB ...
14
votes
1answer
2k views

What hardware device used to eat up 1.4GB of my 4GB RAM, and now suddenly after no hardware changes eats up 2.2GB?

This is more or less a continuation of What hardware device eats up 1.4GB of my 4GB RAM? While I have more or less accepted the solution there that for some mysterious reason, after a BIOS upgrade ...
13
votes
5answers
29k views

How to know if my BIOS supports UEFI?

I recently bought a new Dell notebook for my girlfriend and I want to know if the computer comes with a UEFI BIOS, unfortunately I didnt find any information in the manual or on Windows, is there some ...
13
votes
5answers
93k views

Can I delete the 'EFI System Partition' without harming other data on the drive?

I have three external HDDs in a USB enclosure. After a recent upgrade to Windows 7, during which these three drives were actually installed inside the PC tower, two of the three drives now have a ...
11
votes
4answers
10k views

Hiren's Boot CD with UEFI support?

I am a long term user of Hiren's Boot CD, but the CD does not support booting on UEFI/EFI/SecureBoot hardware, is there some kind of update/patch to apply to the cd image to be able to boot without ...
8
votes
2answers
9k views

Tools to modify UEFI Variables in Windows/Linux?

I have a DELL machine that use Phoenix SecureCore Tiano as its UEFI/BIOS However, it is totally not configurable as its UEFI shell & menus are hidden in BIOS Setup. I'm wondering if there were ...
8
votes
2answers
2k views

How to get rEFInd working with FileVault 2 on OSX 10.8

I installed rEFInd on my new Macbook Air which I planned on using to do a dual boot to Linux, but prior to installing Linux, I decided to encrypt my drive. I knew I was going to do this, so I had ...
7
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2answers
9k views

Do I need to re-install windows 8 to enable UEFI?

I know that UEFI provides for much faster boot up speeds, but as of right now it is disabled in my BIOS. Should I enable it and it'll switch over auto-magically?
7
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2answers
9k views

Windows 7 + Ubuntu dual boot + UEFI BIOS

I received a new Lenovo T420 laptop with Windows 7. The disk now contains: a hidden SYSTEM_DRV boot partition (1.17GB, 400MB used). I'm guessing this is the UEFI partition; the laptop comes with ...
7
votes
1answer
588 views

efi and linux - bootloaders, and any performance advantage?

Modern systems seem to be EFI based, and while there's a specific version of lilo that works with it, i can't seem to find any mention of a efi varient of grub (edit - on modern debian derivative ...
5
votes
1answer
33k views

How to upgrade Mac Pro 1.1 from OS X 10.6.8 to OS X 10.9 Mavericks?

Upgrading the Mac Pro 1.1 2006 in the standard way using the app store is not possible. This is caused by the lack of the 64 bit EFI bios. The hardware of the Mac Pro 1.1 is already complete 64bit ...
5
votes
1answer
577 views

Why isn't rEFInd shell loading?

Because of a two-steps deep problem, I need to boot into an EFI shell and run gptsync. I downloaded the flashdrive binaries of rEFInd 0.7.4, used dd to write the image to a thumbdrive, and it seems ...
4
votes
4answers
22k views

How do I mount the EFI partition on Windows 8.1 so that it is readable and writeable?

Here is what I do: restart machine with Windows 8.1 determine "EFI System" parition with the Disk Management utility run command prompt as administrator type diskpart type select disk 0 then select ...
4
votes
1answer
7k views

How do the 'EFI system partition' and UEFI *.efi files relate?

I read that there needs to be an EFI system partition. The EFI System partition is a partition on a data storage device that is used by machines that adhere to the Extensible Firmware ...
4
votes
4answers
1k views

Convert a GPT disk to MBR from XP

So I took some files with me on my external HDD while going on vacation. Through a series of events, I ended up storing the data in a NTFS formatted partition defined in a GUID Partition Table. The ...
3
votes
2answers
4k views

How to use ATA security on a hard disk in practice?

My SSD HD supports ATA Security. Does Macbook EFI and linux support it? I know hdparm does. Who will do the unlock at each bootup? Can I still set a password without erasing the disk? Update: removed ...
3
votes
1answer
2k views

2.1TB limit on BIOS?

While checking out this 3TB 7200RPM drive as a candidate for my hardware RAID array, I saw the product video and at about 1:40 into the video, the guy says that BIOS can't handle more than 2.1TB of ...
3
votes
1answer
1k views

What are the .efires files on OS X Lion's Recovery HD?

If you mount the Recovery HD that enables OS X Lion File Vault 2, Safari mode, and certain recovery options, you see several .efires files. What format are those and what do they contain?
3
votes
1answer
7k views

How to install Windows with no CD drive boot option in BIOS?

I have a new computer which I built from scratch and I am trying to install a copy of Windows Vista on it. I am able to get to the BIOS and change the boot options which are as follows.. -Built-in ...
3
votes
3answers
772 views

Can BIOS be eventually upgraded to EFI?

I have an Intel PM55 chipset in my notebook. Reportedly Windows 8 (aka Windows Next) will not support BIOS-based systems. Is my motherboard forward-compatible to house an EFI firmware?
3
votes
2answers
3k views

Using VirtualBox with a local Windows 7 installed on the hard drive

I just discovered today that one can create VirtualBox VMDK files that simply reference real partitions on local disks and, needless to say, got pretty excited. "This means I can boot my Windows 7 ...
3
votes
4answers
20k views

How to fix EFI-boot on my Macbook Pro after Ubuntu install?

The MacBook does not boot. The screen stays blank (black) – not the grey, active screen like normal. To power off, I hold the power button down. After 5 boot attempts the MacBook finally shows the ...
2
votes
5answers
14k views

Is there a list of available boot-args for darwin / OS X

In OS X you can set boot parameters with nvram boot-args=[options] Where the options I know about -v (verbose) -x (safe mode) and arch=x86_64 (boot into 64 bit kernel on 64 bit capable machines). ...
2
votes
2answers
978 views

What can an end user do with efi or uefi?

Other than greater support for hardware, what advantage or use could an end user (read: NOT an expert) do with an EFI shell or EFI BIOS? I've seen the shell once on my MacBook Pro, but it seemed ...
2
votes
4answers
3k views

EFI GPT Windows 7 boot-loader/manager issue and grub

My computer(asus N76VM 64 bit) with windows 7 (64 bit home professional) pre-installed got in a bad state while partitioning from a later installed Ubuntu environment. This had lead me to run testdisk ...
2
votes
2answers
922 views

Unable to boot into Windows partitions on early-2008 MacBook Pro using Crucial M225 128gb SSD

I purchased a Crucial CT128M225 SSD on October 19th for my early-2008 17" MacBook Pro this week (Boot ROM: MBP41.00C1.B03). I'm currently running OSX 10.6.1. The Apple EFI 1.7 Firmware Updater says ...
2
votes
3answers
3k views

Bootcamp doesn't boot after resize

I just resized my Windows 7 NTFS partition on my macbook using GParted. Now, when I hold down the option key at startup, this partition doesn't show up. My OS X partition shows up normally. So I can't ...
2
votes
1answer
2k views

Boot ISO from HDD from UEFI?

I have a Windows 8 To Go Entreprise HDD, which boots both on BIOS and UEFI systems (I'm wondering how that's done, because I need that too). Now, I see the HDD I use for that windows is an MBR HDD, ...
2
votes
1answer
1k views

Dual booting Windows 8 and Ubuntu 12.04 with EFI. Got “error: unknown filesystem” and grub rescue prompt

This is a Toshiba Satellite S855-S5381. Windows 8 was already installed and then I installed Ubuntu 12.04 alongside it. During this process I was informed to make sure to turn off Windows fastboot ...
2
votes
1answer
1k views

Trying to boot Kali Linux from USB on Mid 2010 macbook pro

I created a Kali Linux Live USB (MBR with compatibility for both BIOS+EFI) and created an /EFI/BOOT directory on the USB's root directory, with the file bootx64.efi in it. However, when I tried to ...
2
votes
2answers
697 views

Windows 7 GPT to MBR? EFI to BIOS

I want to convert my existing GPT partition table to a MBR one. UEFI is giving me too many headaches with Linux. Actually, I'm just interested in my Windows partition. All the articles on the ...
2
votes
2answers
13k views

Windows 8 EFI boot issue

I've got a simular problem as described in How can I repair the Windows 8 EFI Bootloader?, but with some different details. When I tried to change the bootsequence of my harddisks (of which 1 SSD) in ...
2
votes
1answer
2k views

Linux EFI Live CD/USB

I was trying to boot from CD on a new HP Pavilion dv6 a few days ago with much frustration due to the Linux distributions I tried not working with EFI. Additionally, the EFI Bios is Insyde H20, which ...
2
votes
2answers
2k views

Lost Windows 7 boot after EasyBCD with EFI

I've got a Lenovo Y580 with a 64GB SSD and a 1TB HDD setup using GPT and setup to boot from (U?)EFI. I was trying to get my Linux Mint installation on the Windows boot manager using EasyBCD (I ...
2
votes
2answers
1k views

Update MAC EFI to EFI 2.x

I've been doing a lot of research about installing Windows on Mac - without having a MBR and such. I'm trying to create a pure GPT/EFI system without MBR. Currently, Mac Bootcamp creates a hybrid ...
2
votes
2answers
544 views

EFI Boot: Two independently bootable physical hard drives?

My computer has two physical hard drives. sdd internal hdd0 hdd internal hdd1 The BIOS (EFI) allows the boot either one. Since I never know when one hdd, especially the ssd, stops working, I ...
2
votes
1answer
1k views

Resize EFI system partition

I have a Windows 8 installation on a 500gb hd with the following partitions; Recovery 300mb EFI System Partition (ESP) 100mb Reserved 128mb Primary 145gb Leaving me with free space of 319gb I'm ...
2
votes
0answers
990 views

Windows 7 + Ubuntu dual boot + conversion to GPT

I have received a new Lenovo T420 laptop with Windows 7. The disk now contains: a hidden SYSTEM_DRV boot partition (1.17 gb, 400mb used). I'm guessing this is the EFI partition, the laptop comes ...
1
vote
1answer
616 views

Is the EFI partition and GPT necessary with less than 2 TiB?

I have a 1 TB external USB hard drive that is GUID partitioned with a 100MB FAT32 EFI partition. The thing is that its a 1 terabyte drive. From what I'm aware, the limit is at 2 tebibytes (TiB). ...
1
vote
2answers
1k views

Snow Leopard 64 bits mode (EFI64 Firmware)

How do I get the EFI64 firmware on my iMac 20" (late 2006) with Intel Core 2 Duo?
1
vote
2answers
818 views

Problems with Windows 7 + Windows Server 2008 R2 multibbot on EFI computer

We have a new computer, and I am a bit confused from its new features I don't know from older hardware. It is a high end PC based on socket 2011. I want to use an SSD disk for operating system, and I ...
1
vote
3answers
684 views

Does there exist a native UEFI disk/partition manager?

UEFI has the infrastructure to support complex applications at boot-time. One of the most urgent needs of the hour is a UEFI application for GPT disk management. A lot of partition management cannot ...
1
vote
1answer
4k views

What is the EFI shell?

My BIOS offers me the option to launch an EFI shell, but I have no idea what that is. Does it allow me to turn on CPU flags like VT-x or something similar? Why would I want to use it?
1
vote
1answer
582 views

Does the 'mount' command rely on MBR to detect partitions, or can it use the GPT partition table?

TL:DR I have Mac, which means I have EFI and a GPT formatted disk with a hybrid MBR. I am considering adding a fifth partition; to do this, I will mask my first three GPT partitions with one ...
1
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1answer
620 views

EFI System Partition and unallocated space?

I just got a 3 TB external hard drive (I didn't look closely enough and ended up buying one for Mac but I run Windows 7) and it came with a bunch of software I don't particularly want. I want to ...
1
vote
1answer
4k views

Windows 8 EFI issue

I am trying to install windows 8 on laptop with Raid 0 (stripe) as second system and have following error: Windows can't be installed on drive 0 partition 6 (show details) Details says: Windows ...
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3answers
1k views

What is the maximum number of partitions with EFI?

I was wondering what is the maximum number of partition on an GPT-partitionned drive under Linux. The GPT partition table can contain up to 128 partitions, but the device nodes for /dev/sda? (as ...
1
vote
1answer
510 views

How can I reset my BIOS password on my Acer W3 810 Tablet

I set a BIOS password on my Acer W3 810 Tablet and then forgot the password. How can I reset my BIOS password?
1
vote
1answer
1k views

Trying to Mount EFI boot partition on Windows 7, getting “parameter is incorrect”

Preamble: I'm in kind of a strange situation here. I recently set up my late-2008 MacBook Pro to dual-boot between Windows 7 and OSX, using rEFInd. However, in the rEFInd menu at startup, I am given ...
1
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1answer
109 views

Gray Progress Bar in Macbook Boot caused by Partition Fault

Here's my problem: When I try to load my Macbook it shows the gray progress bar. It takes a while to fill the whole progress and after it Macbook just shuts down. I tried to boot from a recovery ...