The Frequency settings --FSB -- Multiplyer--Must have changed in the bios.
Download and install cpuzhttp://www.cpuid.com/cpuz.php
tell me the name of the processor as it shows on the program and also the following details:
Code Name, Brand ID, Package, Technology, Core Voltage, Specification.
Family, Model, Stepping, Ext. Family, Ext. Model. Revision.
Then I can help you more.