This is normally caused by a hardware problem. Sometimes it's an ACPI problem or an IRQ conflict. Was your computer working previously? If so, what do YOU think caused the problem?
<font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
<font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>