Dell inspiron 8600 won't turn on

yesterday, my computer was in the middle of a chkdisk i switched off the power point because of a thunder storm, to prevent a surge. ironically, i havnt been able to get it to turn on since.
a few things about my inspiron 8600; the power cord had previously been cut and re joined and since then never worked on battery alone. but still always worked on power adapter. is this something to do with the power adapter or a bigger problem? wen i press the power button it lights up for 1-2 seconds then goes dead. the screen flashes for a second then nothing. do i need a new power cord?
thanks in advance for any advice anyone can give...