Ordinateur qui s'éteint avec message d'erreur

Bonjour,

A plusieurs reprises, mon ordinateur s'est éteint subitement avec le message suivant :

A problem has been detected and Windows has been shut down to prevent damage to your computer.

BAD_POOL_HEADER

If this the first time you've seen this stop error screen,restart your computer.
If this screen appears again,follow these step :

Check to make sure any new hardware or software is properly installed.If this is a new installation,as your hardware or software manufacturer for any windows updates you might need.

If problem continu,disable or remove any newly installed harware or softaware.Disable Bios memory options such as caching or shadowing.If you need to use safe mode to remove or disable components,restart your computer,press F8 to select Advanced Startup Options, and then Select Safe Mode.

Technical Information :

STOP : 0x00000019 (0x00000020,0x9C635C70,0x9C635E80,0x08420006)

Collecting data for crash dump....
Initializing disk for crash dump....
Beginning dump of physical memory.
Dumping physical memory to disk : 100
Physical memory dump complete.
Contact your system admin or technical support group for futher assistance.

Que dois-je faire? Je ne voudrai pas faire une mauvaise manip.