i3-3110m 1 core

Good afternoon, faced such problem. I have a processor i3-3110m is available in 2 and 4 cores. Is windows 7 ultimate. Going into the task Manager it shows 1 core. In msconfig also came shows 1 core. In aida64 also shows only 1 core although the title above shows a dualcore.Upon entering the BIOS POPs up a black screen. Do you think the processor marriage? What to do?