Tulisan
ini terinspirasi dari pengalaman penulis sewaktu menginstal sebuah laptop,
laptop tersebut hanya bisa diinstal dengan OS win 8 dan win 10 saja. Hal itu
dikarenakan Laptop terbaru sekarang kebanyakan menggunakan sistem Boot
menggunakan UEFI Bootloader tidak lagi menggunakan BIOS. Sementara Windows 7
hanya bisa menggunakan sistem Boot dengan BIOS dan tidak support dengan UEFI
Bootloader.
Sebenarnya
apa perbedaan antara BIOS dengan UEFI ? Penulis mencoba meringkasnya dalam
sebuah tulisan yang penulis kutip dari sebuah forum dengan nama ‘SuperUser”. Di
dalam forum tersebut ada seorang member yang menanyakan perbedaan antara BIOS
dan UEFI. Pertanyaannya kira-kira seperti ini :
Now Windows 8 supports the UEFI bootloader and I have read that
its different from the BIOS, but it's unclear to me after many searches on the
Google.
Some
points in mind are below:-
·
As we all know, BIOS is an important part of accessing boot
options. So UEFI will do that now? How?
·
How would I know that I'm booting with UEFI not with BIOS?
·
So what is the real difference in the "boot with BIOS"
and "boot with UEFI"?
Dalam
pertanyaan tersebut, beliau menanyakan what is the real difference (Apa
perbedaan sebenarnya antara Boot menggunakan BIOS dengan Boot menggunakan UEFI?
Kemudian
member lain menjawab pertanyaan tersebut dengan sempurna. Jawabannya kira-kira
seperti ini :
·
As we all know that
BIOS is important part for accessing boot option. So now UEFI will do that?
How?
BIOS boots by reading
the first sector on a hard disk and executing it; this boot sector in turn
locates and runs additional code. The BIOS system is very limiting because of
space constraints and because BIOS runs 16-bit code, whereas modern computers
use 32-bit or 64-bit CPUs. By contrast, EFI (or UEFI, which is just EFI 2.x) boots
by loading EFI program files (with .efi filename extensions) from a partition on the
hard disk, known as the EFI System Partition (ESP). These EFI boot loader
programs can take advantage of EFI boot services for things like reading files
from the hard disk.
As a practical matter,
if you're using an OS like Linux that has complex BIOS-mode boot loaders,
EFI-mode booting is likely to be similar to BIOS-mode booting, since GRUB 2
(the most popular BIOS-mode boot loader for Linux) has been ported to work under
EFI, and many Linux distributions install GRUB 2 by default on EFI systems.
OTOH, you can replace or supplement GRUB 2 with other EFI boot loaders. Indeed,
the Linux kernel itself can be an EFI boot loader; code was added to do this
with the 3.3.0 kernel. Used in this way, the EFI itself loads and runs the
Linux kernel, or you can use a third-party boot manager like rEFInd or gummiboot to let you select which OS or kernel to boot.
·
How would I know that
I'm booting with UEFI not with BIOS?
As Root says, there
are clues in the firmware's user interface; however, those are unreliable and
vary from one computer to another. The only way to be sure is to check to see
how the computer booted. In Linux, for instance, the presence of a directory
called /sys/firmware/efi is diagnostic. If it's present, you've booted
in EFI mode; if it's not present, you've probably booted in BIOS mode. (This directory can be
absent on an EFI-mode boot under some circumstances, though.) dmesg output that refers to
EFI is also diagnostic of an EFI-mode boot. In Windows, the partition table of
the boot disk is diagnostic; if it's GPT, you booted in
EFI mode, and if it's MBR, you booted in BIOS mode.
·
So what is the real
different in the "boot with BIOS" and "boot with UEFI"?
EFI can be faster, but that's not certain. The biggest
speed difference is in hardware initialization early in the process. On my
systems, this is a fraction of the total boot time, so a reduction in the
hardware initialization time, while good, doesn't make all that much difference. It's not like I'm rebooting
every ten minutes, after all.
UEFI supports a
feature called Secure Boot that's intended, as the name suggests, to improve security. It
does this by requiring a digital "signature" of boot loaders, which
in turn should require signing of kernels, and so on up the chain. This should
make it harder for malware authors to insert their code into the pre-boot
process, thus improving security. This sounds good, but it also complicates
dual-boot configurations, since code like GRUB and the Linux kernel must be
signed. The major Linux distribution vendors are working on ways to make these
requirements less of a burden for average Linux users, and they've got some
preliminary stuff ready. At the moment, though, disabling Secure Boot is the
easiest way to deal with it. This is a practical concern mainly for brand-new
computers that ship with Windows 8, since Microsoft is requiring Secure Boot be
enabled to get Windows 8 certification. Some people confuse UEFI and Secure
Boot (the latter is just one feature of the former), but it deserves mention as
a difference between BIOS and UEFI because it's causing some problems for new
Windows 8 computers. If you've got an older system or are comfortable enough
with firmware setup utilities to disable Secure Boot, this need not be a real
problem.
Microsoft ties the
boot disk's partition table type to the firmware type (MBR to BIOS; GPT to
UEFI). Because MBR tops out at 2TiB (assuming standard sector sizes), this
means that UEFI is a practical necessity to boot Windows on over-2TiB disks.
You can still use such big disks as data disks under Windows, though, and you
can boot some non-Microsoft OSes (such as Linux and FreeBSD) on big disks using
GPT under BIOS.
As a practical matter
if you're concerned about or interested in UEFI, the biggest issue is simply that
UEFI is new enough that support for it is a bit spotty, particularly in some
older and more exotic OSes. UEFI itself is new enough that most of its
implementations are buggy, and those that aren't vary enough amongst themselves
that it can be hard to describe things generally. Thus, using UEFI can be a
challenge. OTOH, UEFI is the future. It's got some modest advantages, some of which will
become more important in time (such as the 2TiB boot disk limit of Windows).
Switching to a UEFI boot will change a few details of the boot process, but
your overall computing experience won't change all that much once you overcome
any boot issues you may encounter.
EDIT:
Could you expand on
the OpRom settings (Option Rom). They seem to allow you choose between UEFI
booting or "Legacy" booting and they apply to the Video card, Network
card, and various other PCI devices.
Many plug-in cards
provide firmware that interfaces with the firmware on the motherboard. The two
types of firmware must be able to "talk" if the card's firmware is to
do any good. This is necessary to use the card before an OS boots -- for
instance, to display your firmware's options or a boot manager menu on a video
card, to perform a network boot via a network card, or to boot from a hard disk
connected to a disk controller card.
Just as with boot
loaders, the code in a plug-in device's firmware is written to interface with
either BIOS or EFI (although plug-in cards can support both, if I'm not
mistaken). Some EFIs provide options to enable or disable this support on a
fine-grained basis, as you've observed. In some cases, an EFI can use a card's
BIOS-mode support to enable it to work in EFI mode, by "translating"
the calls. (This is common with video cards, for instance; you can often plug
in an old video card with nothing but BIOS support in its firmware and still
use it to boot in EFI mode.)
I don't know precisely
what each of the settings you note does. For instance, I don't know if
"BIOS only" for one of these options would make the card work only in
BIOS mode, "translate" so that the EFI can use the BIOS-mode calls in
EFI mode, or something else. In fact, given the lack of standards in other EFI
user interface areas, I would expect the details to differ from one EFI to
another, so you may need to consult your computer's documentation or experiment
if you need to know the details. I've seen some computers with very
similar-sounding options in two different menus, which further complicates
matters.
·
As we all know that
BIOS is important part for accessing boot option. So now UEFI will do that?
How?
UEFI is a
cross-platform firmware interface that replaces the x86-specific firmware
standard named BIOS. Many UEFI implementations also include a BIOS
compatibility/"legacy" mode, to enable booting from MBRs and
presenting a BIOS-like interface to OSes; however, this is not required by the
standard.
·
How would I know that
I'm booting with UEFI not with BIOS?
If you have a
UEFI-compatible motherboard that offers compatibility/legacy BIOS booting, then
its firmware menu will provide choices such as setting a default boot mode or
even booting single devices in either UEFI or BIOS mode: