i have intel core i7-4510U up to 3.1GHz and when i access to boot advanced options in system configuration i can't change the number of processor.
can you help me please.
I understand that you are trying to "run" the 2nd core of the processor.
Regarding this, I would like to know what is the reason you are trying to run the 2nd core. Also, to mention that the core should run and activate on its own depending on the tasks at hand and the different applications. If the cores appear as inactive in the BIOS then I would recommend you to contact the manufacturer of your system so they can guide you and help you to change settings from the BIOS.
I hope this helps.