The Ultimate Boot CD from www.ultimatebootcd.com (for windows users go to: www.ubcd4win.com ), contains collection of crucial tools and utilities for troubleshooting and fixing your computer problems. If you are bugged with your usual set Computer problems then UBCD is a must-have.
There are tools that let you diagnose problems with your computer and tools to repair those problems. Even if you are not able to boot from your computer hard disk due to a hard drive failure, you can boot from this CD. You can then run diagnostic programs to check the problem.
For Linux users, please follow instructions from UBCD tutorials
For Windows users, find instructions from UBCD4Win