As it turns out, your dad is right.
Extent of Limited Warranty
AMD does not warrant that your AMD processor will be free from design defects or errors known as "errata". A description of the current characterized errata may be found at www.amd.com or is available upon request.
This limited warranty does not cover any costs relating to removal or replacement of any AMD processor or any other cost associated with replacement for the AMD processor.
This limited warranty does not cover damages due to external causes, including improper use, problems with electrical power, accident, neglect, alteration, repair, improper installation, or improper testing.
This Limited Warranty shall be null and void if the AMD microprocessor which is the subject of this Limited Warranty is used with any heatsink/fan other than the one provided herewith.
Notice that OCin as a whole is technically voiding the warranty also...
However, it is very rare for a CPU to die, its MUCH more likely to have a different piece of hardware fail first.
As long as you don't blatantly ignore the max temps and voltages for your CPU, you shouldn't ever have a problem.