Someone? this is a community, am i right?
It would be better and faster and do good for you to get the right answer to your questions if you consult the Dell community. Yes your computer uses Intel's chips but that is all there is to it. The system design is Dell.
Check the list of supported processors for your desktop board, this information usually is posted on the manufacturer website.
Also in order to indeed verify if the processor is defective test it on a different compatible desktop board, this is the list of Intel desktop boards compatible with the E8400 processor
For more assistance you can also contact Dell.