Hello, I want to buy an used laptop computer and I want to know if there's a Good utility for testing all the computer's hardware, I want to burn the utility into a CD and then run it from the CD ROM drive of the laptops I want to test without installing any software on the other's person laptop, I want to be sure that the hardware of that computer is OK, I don't really care too much about the laptop's software 'cause I'm gonna format the hard drive and do a fresh windows install and customize it the way I want to but I need to be sure that memory, mother board, hard drive, etc., are OK, any recommendatios???

Thanks

For the memory, you could use Memtest86+. You can download it as floppy or CD image AFAIK. Additionally, you could try the Microsoft Memory Diagnostic.
As for the HDD, I think the only thing you can do is run a checkdisk and also enable surface scanning. You could also have a look at what Everst says about the SMART values (assuming the HDD supports SMART).

try also cpu-z for information on HW (link)
Like Everst, work in windows from a usb key.
Someone know some other utilities, working without intallation? and from a bootable disc/disk/usb device?
Maybe from a linux live distro?

edit: spelling

Have a look at the Ultimate Boot CD. It contains various applications to check your hardware and much more.

Prime95 can identify memory and CPU instability.

Knoppix can do a live CD boot without install. That will let you exercise to NIC, graphics, etc.

Be sure to check very carefully for even small cracks in the case.

Try using a t-shirt or wash cloth to press gently on the LCD. Look for cracks or irregularities.

You probably don't want to spend all the money for a professional package with connectors for testing the serial and parallel ports.