Usually in the case of ESD your computer won't work anymore. What you're describing doesn't sound like ESD.
This sounds like a possible CPU power or CPU heat issue. Why I say that is because it happened on initial start, and it happened during a virus scan which is CPU intensive.
checklist, don't skip any steps. If you still are having trouble let us know.
It's for no boot issues, but there's alot of stuff in there can can be messed up if you remove your motherboard and hook it up goofy like.