Assuming that you have Windows Vista safely installed
on your computer, you can begin your journey, appropriately enough, at
the beginning: the startup process. After all, the Windows Vista
startup procedure gives new meaning to the term no-brainer: You turn on
your system, and a short while later, Windows Vista reports for duty.
What’s to write about?
You’d be surprised. The
progress of a typical boot appears uneventful only because Windows Vista
uses a whole host of default options for startup. By changing these
defaults, you can take control of the startup process and make Windows
Vista start your way.
The Boot Process, from Power Up to Startup
To better help you
understand your Windows Vista startup options, let’s take a closer look
at what happens each time you fire up your machine. Although a computer
performs dozens of actions during the boot process, most of them appeal
only to wireheads and other hardware hackers. (A wirehead
is, broadly speaking, an expert in the hardware aspects of PCs.) For
our purposes, we can reduce the entire journey to the following 12-step
program:
1. | When
you flip the switch on your computer (or press the Restart button, if
the machine is already running), the system performs various hardware
checks. The system’s microprocessor executes the ROM BIOS code, which,
among other things, performs the Power-On Self Test
(POST). The POST detects and tests memory, ports, and basic devices
such as the video adapter, keyboard, and disk drives. (You hear your
floppy disk motors kick in briefly and the drive lights come on.) If the
system has a Plug and Play BIOS, the BIOS also enumerates and tests the
PnP-compliant devices in the system. If the POST goes well, you hear a
single beep.
| 2. | Now the BIOS code locates the Master Boot Record (MBR), which is the first 512-byte sector on your system’s hard disk. The MBR consists of a small program (the boot code) that locates and runs the core operating system files, as well as a partition table that contains data about the various partitions on your system. At this point, the BIOS code gives way to the MBR’s boot code.
| 3. | On
machines that come with a floppy drive (increasing rare nowadays) the
boot code looks for a boot sector on drive A (the drive light
illuminates once more). If a bootable disk is in the drive, the system
will boot to the A:\ prompt; if a nonbootable disk is in the drive, the
boot code displays the following message:
Non-system disk or disk error Replace and press any key when ready
If no disk is in the drive, most modern systems will then check
for a bootable disc in the CD or DVD drive. If there’s still no joy, the
boot code turns its attention to the hard disk and uses the partition
table to find the active (that is, bootable) partition and its boot
sector (the first sector in the partition).
| 4. | With
the boot sector located, the MBR code runs the boot sector as a
program. The Windows Vista boot sector runs a program called Windows
Boot Manager (BOOTMGR).
| 5. | Windows Boot Manager switches from Real mode (a single-tasking mode in which the processor can access only the first 640KB of memory) to Protected mode (a multitasking mode in which the processor can access all memory locations).
| 6. | Windows Boot Manager reads the Boot Configuration Data (BCD) and displays the Windows Boot Manager menu . Note, too, that at this point you can invoke the Advanced Options Menu for custom startups.
| 7. | Windows
Boot Manager queries the BIOS for information about the system
hardware, including the system buses, the disk drives, the ports, and
more, and then stores the data in the Windows Vista Registry (in the HKEY_LOCAL_MACHINE\HARDWARE key).
| 8. | The Starting Windows
message and the progress bar appear. The progress bar tracks the
loading of the device drivers that Vista needs at startup. The bar
advances each time a driver is loaded.
| 9. | Windows Boot Manager loads the Windows kernel—NTOSKRNL.EXE—which handles the loading of the rest of the operating system.
| 10. | The kernel launches the Session Manager—SMSS.EXE—which initializes the system environment variables and starts the Windows logon process by running WINLOGON.EXE.
| 11. | If
your system has multiple user accounts or a single user account
protected by a password, Windows Vista displays the Welcome screen to
prompt you to pick a user or type your password.
| 12. | New Plug and Play devices are detected and the contents of the Run Registry key and the Startup folder are processed.
|
Windows Vista also provides several routes for personalizing your startup:
Invoke the Windows Vista Startup menu when the POST is complete Edit the BCD to change the default startup options Add programs or documents to the Windows Vista Run Registry key Add programs or documents to the Windows Vista Startup folder
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