Windows 7: Windows 7 64 bit suddenly only recognizes one core.

Hey everyone

i am new here,
at all other forums they tought this question is nonsense

I have a weird problem with my laptop.
my laptop is a dell latitude d630 with an intel core 2 duo T7300 cpu
it is a dual core cpu



but since 2 days my computer runs slower. i didn't understand.
using cpu-z i saw that my cpu only has ONE core.

i do not understand.
can cores go bad separate?

thanks for your help,

greetzz, Dominique

never mind i didnt get reactions. my cpu is already burned. i'll just buy a new one.
thanks for the help