computer tricks

Boot Block Recovery For Free

2011-04-21T10:52:00.001-07:00

You don't need to pay a measly sum of dollars just to recover from a boot block mode. Here it is folks:

AWARD Bootblock recovery:

That shorting trick should work if the boot block code is not corrupted, and it should not be if /sb switch is used when flashing the bios (instead of /wb switch).

The 2 pins to short to force a checksum error varies from chip to chip. But these are usually the highest-numbered address pins (A10 and above).

These are the pins used by the system to read the System BIOS (original.bin for award v6), calculate the ROM checksum and see if it's valid before decompressing it into memory, and subsequently allow Bootblock POST to pass control over to the System BIOS.

You just have to fool the system into believing that the System BIOS is corrupt. This you do by giving your system a hard time reading the System BIOS by shorting the 2 high address pins. And when it could not read the System BIOS properly, ROM Checksum Error is detected "so to speak" and Bootblock recovery is activated.

Sometimes, any combination of the high address pins won't work to force a checksum error in some chips, like my Winbond W49F002U. But shorting the #WE pin with the highest-numbered address pin (A17) worked for this chip. You just have to be experimentative if you're not comfortable with "hot flashing" or "replacement BIOS".

But to avoid further damage to your chip if you're not sure which are the correct pins to short, measure the potential between the 2 pins by a voltmeter while the system is on. If the voltage reading is zero (or no potential at all), it is safe to short these pins.

But do not short the pins while the system is on. Instead, power down then do the short, then power up while still shorting. And as soon as you hear 3 beeps (1 long, 2 short), remove the short at once so that automatic reflashing from Drive A can proceed without errors (assuming you had autoexec.bat in it).

About how to do the shorting, the tip of a screwdriver would do. But with such minute pins on the PLCC chip, I'm pretty comfortable doing it with the tip of my multi-tester or voltmeter probe. Short the pins at the point where they come out of the chip.

AMIBIOS Recovery bootblock:
1. Copy a known working BIOS image for your board to a floppy and rename it to AMIBOOT.ROM.
2. Insert the floppy in your system's floppydrive.
3. Power on the system while holding CTRL+Home keys. Release the keys when you hear a beep and/or see the floppy light coming on.
4 . Just wait until you hear 4 beeps. When 4 beeps are heard the reprogramming of the System Block BIOS went succesfull, so then you may restart your system.

Some alternative keys that can be used to force BIOS update (only the System Block will be updated so it's quite safe):
CTRL+Home= restore missing code into system block and clear CMOS when programming went ok.
CTRL+Page Up= restore missing code into system block and clear CMOS or DMI when programming went ok.
CTRL+Page Down= restore missing code into system block and do not clear CMOS and DMI area when programming went ok
Btw: the alternative keys work only with AMIBIOS 7 or higher (so for example an AMI 6.26 BIOS can be only recovered by using CTRL+Home keys).
Boot Block Recovery for FREE

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BLACKOUT Flashing
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Recovering a Corrupt AMI BIOS chip
With motherboards that use BOOT BLOCK BIOS it is possible to recover a corrupted BIOS because the BOOT BLOCK section of the BIOS, which is responsible for booting the computer remains unmodified. When an AMI BIOS becomes corrupt the system will appear to start, but nothing will appear on the screen, the floppy drive light will come on and the system will access the floppy drive repeatedly. If your motherboard has an ISA slot and you have an old ISA video card lying around, put the ISA video card in your system and connect the monitor. The BOOT BLOCK section of the BIOS only supports ISA video cards, so if you do not have an ISA video card or your motherboard does not have ISA slots, you will have to restore your BIOS blind, with no monitor to show you what’s going on.

AMI has integrated a recovery routine into the BOOT BLOCK of the BIOS, which in the event the BIOS becomes corrupt can be used to restore the BIOS to a working state. The routine is called when the SYSTEM BLOCK of the BIOS is empty. The restore routine will access the floppy drive looking for a BIOS file names AMIBOOT.ROM, this is why the floppy drive light comes on and the drive spins. If the file is found it is loaded into the SYSTEM BLOCK of the BIOS to replace the missing information. To restore your BIOS simply copy a working BIOS file to a floppy diskette and rename it AMIBOOT.ROM, then insert it into the computer while the power is on. The diskette does not need to be bootable or contain a flash utility. After about four minutes the system will beep four times. Remove the floppy diskette from the drive and reboot the computer. The BIOS should now be restored.

Recovering a Corrupt AWARD BIOS
With AWARD BIOS the process is similar but still a bit different. To recover an AWARD BIOS you will need to create a floppy diskette with a working BIOS file in .BIN format, an AWARD flash utility and an AUTOEXEC.BAT file. AWARD BIOS will not automatically restore the BIOS information to the SYSTEM BLOCK for this reason you will need to add the commands necessary to flash the BIOS in the AUTOEXEC.BAT file. The system will run the AUTOEXE.BAT file, which will in turn flash the BIOS. This is fairly easy. Here are the steps you need to take.

· Create a bootable floppy diskette
· Copy the BIOS file and flash utility to the diskette
· Create an text file with any standard text editor and add the following lines

@ECHO OFF
FLASH763 BIOSFILE.BIN /py

In the above example I am assuming that you are using the FLASH763.EXE flash utility. You will need to replace the FLASH763 with the name of whatever flash utility you are using, and replace the BIOSFILE.BIN with the name of the BIOS file you are using. You will also need to change the ‘/py’ to whatever the command is for your flash utility to automatically program the BIOS without user intervention. If you do not know the command to automatically flash your BIOS type the name of the flash utility with a space and then /? to display the utility’s help screen. The help screen should pecify the command switch to automatically flash your BIOS. If you are using the FLASH763.EXE utility then the switch to automatically flash your BIOS is ‘/py’.

What is Bandwidth?

2011-04-21T10:47:00.000-07:00

This is well written explanation about bandwidth, very useful info.

BandWidth Explained

Most hosting companies offer a variety of bandwidth options in their plans. So exactly what is bandwidth as it relates to web hosting? Put simply, bandwidth is the amount of traffic that is allowed to occur between your web site and the rest of the internet. The amount of bandwidth a hosting company can provide is determined by their network connections, both internal to their data center and external to the public internet.

Network Connectivity

The internet, in the most simplest of terms, is a group of millions of computers connected by networks. These connections within the internet can be large or small depending upon the cabling and equipment that is used at a particular internet location. It is the size of each network connection that determines how much bandwidth is available. For example, if you use a DSL connection to connect to the internet, you have 1.54 Mega bits (Mb) of bandwidth. Bandwidth therefore is measured in bits (a single 0 or 1). Bits are grouped in bytes which form words, text, and other information that is transferred between your computer and the internet.

If you have a DSL connection to the internet, you have dedicated bandwidth between your computer and your internet provider. But your internet provider may have thousands of DSL connections to their location. All of these connection aggregate at your internet provider who then has their own dedicated connection to the internet (or multiple connections) which is much larger than your single connection. They must have enough bandwidth to serve your computing needs as well as all of their other customers. So while you have a 1.54Mb connection to your internet provider, your internet provider may have a 255Mb connection to the internet so it can accommodate your needs and up to 166 other users (255/1.54).

Traffic

A very simple analogy to use to understand bandwidth and traffic is to think of highways and cars. Bandwidth is the number of lanes on the highway and traffic is the number of cars on the highway. If you are the only car on a highway, you can travel very quickly. If you are stuck in the middle of rush hour, you may travel very slowly since all of the lanes are being used up.

Traffic is simply the number of bits that are transferred on network connections. It is easiest to understand traffic using examples. One Gigabyte is 2 to the 30th power (1,073,741,824) bytes. One gigabyte is equal to 1,024 megabytes. To put this in perspective, it takes one byte to store one character. Imagine 100 file cabinets in a building, each of these cabinets holds 1000 folders. Each folder has 100 papers. Each paper contains 100 characters - A GB is all the characters in the building. An MP3 song is about 4MB, the same song in wav format is about 40MB, a full length movie can be 800MB to 1000MB (1000MB = 1GB).

If you were to transfer this MP3 song from a web site to your computer, you would create 4MB of traffic between the web site you are downloading from and your computer. Depending upon the network connection between the web site and the internet, the transfer may occur very quickly, or it could take time if other people are also downloading files at the same time. If, for example, the web site you download from has a 10MB connection to the internet, and you are the only person accessing that web site to download your MP3, your 4MB file will be the only traffic on that web site. However, if three people are all downloading that same MP at the same time, 12MB (3 x 4MB) of traffic has been created. Because in this example, the host only has 10MB of bandwidth, someone will have to wait. The network equipment at the hosting company will cycle through each person downloading the file and transfer a small portion at a time so each person's file transfer can take place, but the transfer for everyone downloading the file will be slower. If 100 people all came to the site and downloaded the MP3 at the same time, the transfers would be extremely slow. If the host wanted to decrease the time it took to download files simultaneously, it could increase the bandwidth of their internet connection (at a cost due to upgrading equipment).

Hosting Bandwidth

In the example above, we discussed traffic in terms of downloading an MP3 file. However, each time you visit a web site, you are creating traffic, because in order to view that web page on your computer, the web page is first downloaded to your computer (between the web site and you) which is then displayed using your browser software (Internet Explorer, Netscape, etc.) . The page itself is simply a file that creates traffic just like the MP3 file in the example above (however, a web page is usually much smaller than a music file).

A web page may be very small or large depending upon the amount of text and the number and quality of images integrated within the web page. For example, the home page for CNN.com is about 200KB (200 Kilobytes = 200,000 bytes = 1,600,000 bits). This is typically large for a web page. In comparison, Yahoo's home page is about 70KB.

How Much Bandwidth Is Enough?

It depends (don't you hate that answer). But in truth, it does. Since bandwidth is a significant determinant of hosting plan prices, you should take time to determine just how much is right for you. Almost all hosting plans have bandwidth requirements measured in months, so you need to estimate the amount of bandwidth that will be required by your site on a monthly basis

If you do not intend to provide file download capability from your site, the formula for calculating bandwidth is fairly straightforward:

Average Daily Visitors x Average Page Views x Average Page Size x 31 x Fudge Factor

If you intend to allow people to download files from your site, your bandwidth calculation should be:

[(Average Daily Visitors x Average Page Views x Average Page Size) +
(Average Daily File Downloads x Average File Size)] x 31 x Fudge Factor

Let us examine each item in the formula:

Average Daily Visitors - The number of people you expect to visit your site, on average, each day. Depending upon how you market your site, this number could be from 1 to 1,000,000.

Average Page Views - On average, the number of web pages you expect a person to view. If you have 50 web pages in your web site, an average person may only view 5 of those pages each time they visit.

Average Page Size - The average size of your web pages, in Kilobytes (KB). If you have already designed your site, you can calculate this directly.

Average Daily File Downloads - The number of downloads you expect to occur on your site. This is a function of the numbers of visitors and how many times a visitor downloads a file, on average, each day.

Average File Size - Average file size of files that are downloadable from your site. Similar to your web pages, if you already know which files can be downloaded, you can calculate this directly.

Fudge Factor - A number greater than 1. Using 1.5 would be safe, which assumes that your estimate is off by 50%. However, if you were very unsure, you could use 2 or 3 to ensure that your bandwidth requirements are more than met.

Usually, hosting plans offer bandwidth in terms of Gigabytes (GB) per month. This is why our formula takes daily averages and multiplies them by 31.

Summary

Most personal or small business sites will not need more than 1GB of bandwidth per month. If you have a web site that is composed of static web pages and you expect little traffic to your site on a daily basis, go with a low bandwidth plan. If you go over the amount of bandwidth allocated in your plan, your hosting company could charge you over usage fees, so if you think the traffic to your site will be significant, you may want to go through the calculations above to estimate the amount of bandwidth required in a hosting plan.

How to rename the Microsoft Windows Recycle Bin

2011-04-21T10:45:00.000-07:00

Click Start / Run

Type regedit and press enter.
Open the HKEY_CLASSES_ROOT folder
Open the CLSID folder
Open the {645FF040-5081-101B-9F08-00AA002F954E} folder
Open the ShellFolder folder
Change the Attributes data value from 40 01 00 20 to 50 01 00 20. Once completed change the CallForAttributes dword value to 0x00000000 (double-click and change value data to 0). You must change both of these values to get the rename to appear.

How to remove virus manually?

2011-04-21T10:44:00.000-07:00

To create a basic batch file in MS-DOS, follow the below steps that give you an example of how to create a basic batch file.

Open an MS-DOS command window or get to MS-DOS. Additional information about doing this can be found on document CHDOS.
At the MS-DOS prompt, type: edit test.bat and press enter.
If typed properly, you should now be in a blue screen. Within the screen, type:

pause
dir c:\windows
dir c:\windows\system
Once the above three lines have been typed in, click File and choose exit; when prompted to save, click "Yes." Users who do not have a mouse cursor can accomplish this same task by pressing ALT+F to access the file menu, then pressing "X" to exit, and pressing enter to save changes.
Once you are back at the MS-DOS prompt, type: test and press enter. This will execute the test.bat file and begin running the file. Because the first line is pause, you will first be prompted to press a key. Once you press a key the batch file will run line-by-line; in this case, listing the files in the windows and windows\system directories.

Creating a batch file

2011-04-21T10:43:00.001-07:00

To create a basic batch file in MS-DOS, follow the below steps that give you an example of how to create a basic batch file.

Open an MS-DOS command window or get to MS-DOS. Additional information about doing this can be found on document CHDOS.
At the MS-DOS prompt, type: edit test.bat and press enter.
If typed properly, you should now be in a blue screen. Within the screen, type:

pause
dir c:\windows
dir c:\windows\system
Once the above three lines have been typed in, click File and choose exit; when prompted to save, click "Yes." Users who do not have a mouse cursor can accomplish this same task by pressing ALT+F to access the file menu, then pressing "X" to exit, and pressing enter to save changes.
Once you are back at the MS-DOS prompt, type: test and press enter. This will execute the test.bat file and begin running the file. Because the first line is pause, you will first be prompted to press a key. Once you press a key the batch file will run line-by-line; in this case, listing the files in the windows and windows\system directories.

How To Create a Prank Virus

2011-04-21T10:37:00.000-07:00

1.>Open notepad and type:-

@echo off

echo YOU HAVE A VIRUS ON YOUR COMPUTER

pause

echo CONTATTING ANTIVIRUS

pause

echo DO YOU WANT TO DELETE ANTIVIRUS?

pause

echo ACCESS DENIED

pause

echo ACTIVATING VIRUS

echo VIRUS ACTIVATED

pause

dir/s

goto 1

· Save it as: """"""""".bat

Tip 3: Windows Xp Secret Song

· Go to My Computer

· Open Folder Images and search a file called: "title"

· Open the file and enjoy the windows xp secret song