Physcial Memory Dump

I have had a blue screen message that says something like “beginning physcial dump…” Driver IRQL_NOT_LESS_OR_EQUAL TO”….and a bunch of other code. Once it counts up to about 95 it reboots and works fine. Sometimes I get a similiar message on start up (c: and/or D: drive) and it is checking the disks for consistency. Any idea of what this could be or what I should do? Or not do? Thanks.