About Technology

Windows Vista Boot Process Overview

By:Arun

The Windows Vista™ boot process differs from Windows® XP in the way the operating system is located and initialized. Start-up begins with the BIOS loading the Master Boot Record (MBR) on the bootable disk. The MBR in turn loads the Partition Boot Record (PBR) on the active partition. So far, Windows Vista remains relatively unchanged.

Windows Vista is different from XP starting by the fact the PBR code written by Windows Vista no longer looks for Ntldr. The new boot loader in Windows Vista is Bootmgr. This component loads the Boot Configuration Database (BCD), which in turn loads an OS loader boot application (Winload.exe, in the case of Windows Vista). Finally, the OS loader application is responsible for initializing the kernel. This process is illustrated below.

You can think of this change in two elements:

The two key actions performed by Ntldr in previous Windows versions have been divided between two components:

1. Bootmgr reads the boot configuration, including device and path locations.

2. WindowsSystem32Winload.exe initializes the kernel.

The boot configuration stored by Boot.ini in previous Windows versions is now stored in an extensible database, BootBCD, the Boot Configuration Database (BCD).

These changes are significant because of the impact they have:

1. The boot process can be extended to support other applications, such as other operating systems or other versions of the OS.

2. Only nonversion-specific components are stored in the root of the active partition. This means that theoretically Windows Vista could be installed on a machine running some future Windows version with the same boot structure, and it would not break the boot process for that future version. With legacy Windows, installing an older Windows version last causes the newer version to fail on start-up. This is due to version-specific code improvements in Ntldr.

3. Tool-oriented boot entries can be supported to offer maintenance options on boot when a previous start-up failed. In the past, Windows supported an menu provided by a target operating system. This new structure can make tools available earlier during the boot process, meaning that they are available even if all OS-specific boot entries are damaged. The Windows Memory Diagnostic tool is provided in the boot menu in this way.

BCD Store

The Boot Configuration Data (BCD) store contains boot configuration parameters and controls how the operating system is started in Microsoft Windows Vista operating system. These parameters were previously in the Boot.ini file in BIOS-based operating systems or in the nonvolatile RAM (NVRAM) entries in Extensible Firmware Interface-based operating systems. You can use the Bcdedit.exe command line tool to affect the Windows code which runs in the pre-operating system environment by adding, deleting, editing, and appending entries in the BCD store. Bcdedit.exe is located in the WindowsSystem32 directory of the Windows Vista partition.

The BCD is a database used by Bootmgr. It contains the functions of Boot.ini and is located in the {ActivePartition}boot folder

Bcdedit.exe

You can use Bcdedit.exe to modify the Windows code which runs in the pre-operating system environment by adding, deleting, editing, and appending entries in the BCD store. Bcdedit.exe is located in the WindowsSystem32 directory of the Windows Vista partition.

Boot.ini Compared to BCD

BCD eliminates the need for Boot.ini in Windows Vista, although Boot.ini is still present on dual-boot systems for backwards compatibility. Because the BCD boots to the boot environment first instead of Ntldr, the location of Ntldr is not verified unless a legacy operating system is chosen.

Configuration Tools

The BCD store can be modified or repaired using several tools:

System Properties in Control Panel

SystemPropertiesAdvanced.exe

Msconfig

Windows Recovery Environment (WinRE) Startup Repair

Bcdedit.exe

Bootrec.exe

Most of these tools enable you to perform simple tasks, such as setting a boot menu timeout, setting a default operating system, or configuring boot options such as /SOS and /SAFEBOOT. Others are repair-oriented tools; Startup Repair and Bootrec.exe, in particular, provide automated mechanisms for fixing problems in the BCD.

Bcdedit.exe is the main tool for detailed BCD store modifications. You can use Bcdedit to change Bootmgr options; add boot, delete, and edit boot entries; import and export the BCD store; and create a new store if it becomes significantly damaged. Bcdedit.exe is located in the WindowsSystem32 directory of the Windows Vista partition and is also available in WinRE.

BCD Store Location

The BCD store is a registry hive, stored as BootBCD on the active partition. This hive is loaded but hidden from view in Regedit.exe within Windows Vista. The store is loaded to the following registry location: HKLMBCD00000000.

You can also view the store manually in WinRE by loading the hive from the Boot folder. To obtain a copy of the hive on a running system, use the Bcdedit /export filename command to export a hive file for offline examination. This command exports the BCD store to a file called filename in the current directory.

Related Components

Msconfig

Msconfig is the preferred PSS UI tool for managing boot settings. The tool supports BCD and allows the user to enumerate all BCD objects in the system store. It allows certain elements to be altered for each OS object, including debug settings, safe mode settings, and other popular PSS options. It cannot be used with the WinRE console; Bcdedit needs to be used in these cases.

Bcdedit.exe

Bcdedit.exe is a command line tool that can be used to manage BCD settings. In summary, Bcdedit.exe is a replacement for Bootcfg.exe. However, it is enhanced for better scripting and to expose some of the more powerful features of BCD that bootcfg.exe did not expose for manipulating Boot.ini. Bcdedit.exe is designed to work on previous operating systems and in recovery environments.

For more details on this topic please go to www.wintechhelp.com

Source: http://www.articlesbase.com

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How To Prevent Your Computer From Slowdowns

by: Subhash Kumar

Prevention of your computer from slowdowns effects the performance of your computer, because if your computer working with proper speed, it definitely increases your efficiency and working speed. These are the guidelines given below which will help to maintain your computers speed:

•Fragmented hard drive is the biggest bottlenecks of all. Disk fragmentation can significantly slow down your machine. A common cause of disk fragmentation is a disk that is too full. You should keep 20 percent to 25 percent of your hard disk space free to minimize file fragmentation and to improve the defragmenter’s ability to defrag the disk. Thus, if a disk is too full, move some files off the drive and restart the defragmenter. Once you defrag (defragment) your hard drive, you may notice an immediate and significant increase in system performance.

•Ensure antivirus software is installed, automatically checking for updates, and automatically scanning all incoming files. If there is a virus associated with a new file it will automatically be repaired or quarantined. New viruses come out daily. Because of this, the anti-virus software needs to be configured to automatically updates it's self.

•When Windows boots up, one of the first things it does is check the Fonts folder and then load all of the fonts present so that they will be accessible from whatever applications you are running. The problem is that all of those fonts eat up resources, and they slow down your system, especially on boot up. To over come this problem open my computer, then double-click the Control Panel icon, and then the Fonts folder. The system will display a list of all of the fonts currently installed on your computer. Double-click any font to see examples of it. If it looks like something you will never use, select and then delete it.

•One often-ignored culprit of system slowdown is the machine’s BIOS settings. Slowdowns may occur if the BIOS settings do not match the optimal machine configuration. Often you can improve machine performance by researching your motherboard’s optimal BIOS settings, which may not be the same as the factory defaults.

There is no centralized database of optimal BIOS settings, but you can employ a search engine such as Google or AllTheWeb and use your motherboard name and BIOS as keywords to find the correct settings.

•Read the terms and conditions before signing up for or downloading anything for free on the Internet. Free downloads like Kazaa (music), games, toolbars, and coupons often come with adware or spyware. The terms and conditions of downloads explain adware will be installed on the persons machine in exchange for the free software, music, pizza or whatever. Of course, few people read these terms and conditions.

•Multitasking was a boon for which we had been waiting for years. Suddenly, we could actually set the computer to a task and that task could continue while we did something else, such as work on a document or browse another Web site. Microprocessors, even today's more powerful ones, can only do so much before they begin to bog down. If you have multiple applications open, especially if they are each working on tasks, overall speed will suffer; the multiple tasks will indeed get processed, but that processing will take place more slowly than if any one of the activities were the only one taking place.

•Modern processors generate a lot of heat. That’s why all processors require some sort of cooling element, typically a fan of some type. When the processor temperature goes over spec, the system can slow down or run erratically.

•Install a hardware firewall to keep hackers out. Hackers have automated tools that are looking for any PC connected to the Internet without a firewall. If you are connected to the Internet but don't have a firewall, hackers (criminals) will be in your PC. Beyond stealing your information they can install programs that can damage or slow your PC down. A hardware firewall to protect all the PCs on the local area network provides the best protection. Recommended hardware firewalls are Linksys, Netgear, and D-link.

•Your computer is a complex system comprising many pieces of hardware and software, all of which must work well together for optimum results. Eliminating the bottlenecks that result in system slowdowns is one major step in that process.

If you follow the above prevention, definitely your computer running better. We suggest doing these things yourself or schedule a computer professional to proactively perform and ensure these preventive maintenance steps are in place and working on a monthly basis. This will prevent computer slowdowns.

About the Author:

and Subhash Kumar SEO Manager For more details on Computer Slowdowns visit our http://www.halfvalue.comhttp://www.halfvalue.co.uk websites.

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How To Correct A Continually Rebooting Computer

By: Otis Cooper

When you sit down at your computer desk and press the power switch on your desktop, the last thing you want to experience is a continually rebooting computer.

There are a variety of causes that contribute to this problem, from something as simple as a stuck power button to a much more serious problem as your power supply slowly failing. Other causes for this problem may be overheating PC components, or viruses affecting your system.

Now, if you’re like the rest of us, having a computer that reboots constantly is not our idea of a productive day. So how do you diagnose this problem and where do you start to to make corrections. Here are some common but often overlooked causes and solutions that will get your system running again.

First take a look at the power button and see if its stuck in the socket. If so, you may be able to simple tap the front of the case to release the button. In some cases, you may have to remove the system unit cover to get the button to return to the out position.

If you cannot stop the computer from rebooting by pressing the power button and releasing it, turn off the power switch in the back of the computer next to the power supply. If your power supply do not have a power switch, you will have to unplug the system from the wall outlet.

This must be done as soon as possible so that the constant rebooting will not damage components such as the hard drive. Constant rebooting also have the danger of power surges that can further damage larger components such as the motherboard.

Second you check your computer’s software by checking to be sure no virus or malware have not effected your hard drive. Virus and malware are small software that is downloaded along with other files that is designed to cause mischief.

To remove any viruses and malware, use a anti-virus program that will search your hard drive and remove these file quickly. These files can cause such damage as wiping your hard drive of all data or hijacking your web browser so you have no control over your online surfing.

If you find no malware on your computer, take a look at your BIOS to see if it has become unstable or has been changed. BIOS stands for Basic Input Output System and is a small program designed to check all components for proper operation when the computer is turned on.

If your BIOS has been changed or if you’re not sure if its been changed, try to reset the BIOS settings to the default settings after you access the BIOS as the computer reboots.Once inside the BIOS, you should have the option to load your default settings, save the change, and reboot the computer.

However, there are times when a continually rebooting computer will not allow you to access the BIOS. You can then reset the BIOS by removing the system unit cover and locating the jumper on a three pin header.

You must consult your computer or motherboard manual to properly perform this procedure and it should be done as a last resort. Before making any changes to your BIOS, you should backup your BIOS if your computer reboots at long intervals.

After checking your computer’s software for its rebooting problem, you must check to be sure hardware is not at fault. This problem may exist because one of your memory modules are unseated from its socket . Memory modules are long, narrow sticks that attach to the motherboard.

Remove any static electricity from yourself, remove the system unit cover and check these memory modules to be sure they are secure. Check the connections to the hard drive and the connections leading from the power supply.

Power supply connectors should be checked if you’ve done work inside your computer recently. Power Supplies are known to slowly fail and lead to rebooting problems. There is no way to check an ailing power supply and this should be considered the problem as a last resort.

Following these steps will help you correct any computer that continually reboots itself. If no virus or malware is found, carefully and thoroughly check all connections. And if the problem still exist, the most likely cause would be the Power Supply.

About the Author:

Otis F. Cooper is solely dedicated to boosting the knowledge and confidence of every computer user. Sign up to receive his informative articles every month and learn PC Repair absolutely free.Sign up now at http://www.ultimatepcrepair.com

No Comment | Posted in » BIOS, constant rebooting, Continually Rebooting, hardware, jumper, malware, power supply, socket, virus    

Hard Disk Detection Problem With BIOS

By:Ravi chamria

During POST (Power On Self Test), the BIOS try to get information about all the devises
Connected to the system. After checking the processor and RAM it checks for devise such you’re hard disk, CD-ROM, etc., and display them on screen with messages such as ‘detecting IDE drives…’ and Found Primary Master….’etc. Sometimes your BIOS Just refuses to recognize your hard disk, basically making it useless-there’s no way windows will recognize your hard disk if the BIOS doesn’t. Let’s see why this happens:

The most common reason is a loose or badly connected data cable. Make sure the data cable is plugged in properly, both into the hard disk, as well as the motherboard. The same goes for power cable, so check that as well. Also, make sure that the red lines on the data cable and power cable are adjacent to each other.

One you’ve ruled out any cable problems, check the jumper setting on the drives. If two drives are connected to a port, make sure one is set as master and the other as Slave, or else both are set to Cable Select.

Next, make sure your drive controllers on your motherboard are not disabled. These controllers control IDE devices, and without them the BIOS cannot detect the drives. Go to the BIOS setup, and under the Integrated Peripherals menu, make sure that ‘On Board HDC’ is enabled for both Primary and Secondary channels. Also ensure that all drive types are set to AUTO under the Standard CMOS Setting. If you are not comfortable with changing the BIOS values, just reset the BIOS to factory defaults.

When all else fails, so has your hard disk send it to a technician for servicing.
During POST (Power On Self Test), the BIOS try to get information about all the devises Connected to the system. After checking the processor and RAM it checks for devise such you’re hard disk, CD-ROM, etc., and display them on screen with messages such As ‘detecting IDE drives…’ and Found Primary Master….’etc. Sometimes your BIOS Just refuses to recognize your hard disk, basically making it useless-there’s no way windows will recognize your hard disk if the BIOS doesn’t. Let’s see why this happens:

Ravi chamria is a webmaster, for more computer related articles please visit at Computers-and-Technology

Article Source: http://www.eArticlesOnline.com

No Comment | Posted in » badly connected data cable, BIOS, BIOS cannot detect the drives, IDE drives, On Board HDC, Power On Self Test