I'd say in general it's not the INTENT of viruses to destroy the hardware.
The virus wants to get your information, or use your PC's resources.
As a result of utilizing your PC's resources it could damage your hardware.
Example: A virus infects your PC, and continuously downloads/uploads files.
That could destroy your Hard Drive eventually by having it consistently run 24/7, especially if it was in a poorly ventilated laptop.
Or a bug can ruin hardware as well. Example of this is there used to be a bug in WMP (May still be there), that would download metadata for WMP. However, it would sometimes freak out, and continually download metadata files for CDs. Left unchecked, it would download MILLIONS of 1 byte files which is not only terrible for your HDD, but when you tried to open the directory to delete the files, it would lock the PC up making it almost impossible to delete the files. Deleting the files took days to finish.
You could have a virus where it's utilizing your PC's CPU to brute force a password. That would keep your CPU running at 100% constantly which shouldn't fry your CPU since your CPU should downclock and has safety measures to save it but in combination with other things (like bad ventilation, or maybe your CPU fan fails after running at 100% speed consistently), it may fail.
It's not something I'd worry about though if I was you....