Depends what your motherboard is. The BIOS will limit what you can upgrade to. You are likely to be able to upgrade to a Phenom II CPU of some sort.
The FX CPU is out of the question unless you have an AM3+ socket motherboard.
Providing the make and model of your motherboard would help others give you advice.
he bios is Award Modular BIOS v6.00PG my socket is amd3
the mother board specs this is my specs Gigabyte Technology co ltd model m68mt-s2p ,chipset nvidia Geforce 7025 rev A3
Southbridge nvidia nforce 630a Rev2,Lpcio ite it8720 an graphic card is AMD Radeon HD 6850 Series