NOT having swap enabled increases the risk of a kernel crash ("random reboot") - even more so on the 770, as it is twice as fast at running out of memory to a degree where some critical process cannot allocate memory any more.

The contents of the kernel file are irrelevant - there is no need to clear or rebuild it, ever, as any page copied over from memory will by the very principle of paged memory overwrite whatever that segment of the swap space may have previously contained.

Sevo