eMac -Software to test hardware!!!!

As I wrote on this thread : http://www.mac-forums.com/forums/showthread.php?t=35194

So many persons came to me with so many causes.. the hardrive, memory, video card...

If it's a software problem, i'm sure I will get rid of it while starting the eMac from zero.. but for Harware ??? Before searching what 's the cause of all my problems in the applications, I want to be sure that everythings going fine in my hardware.. SO SOMEBODY KNOWS SOMETHING THAT WILL CHECK MY CPU, MEMORY, VIDEOCARD ETC... LIKE DOCTOR NORTHON WAS DOING IN OS9 ?????

boot from cd and slect hardware check or somethign like that....

i thnk its called "apple hardware test"

Yeah 'Apple hardware test' it will push every component to the max and test it that even included the fans.