There are some specifications we need to follow before make any processor’s upgrade or downgrade like: processor socket type, voltages and stepping (microcode). The best way to go is get a list of compatible processors for your notebook directly from the system manufacturer (DELL*) to prevent any incompatibility, even though let me give a list of Intel® Core™ i7 mobile Processor 1st with a the socket type 988:
Thank you for your responses. On the weekend I removed my i7740qm processor from my alienware notebook and installed it in my dell vostro 3750 notebook. Both have the 988 socket. Due to the different fsb and other differences it did not work! So that answered that question once and for all. Thanks to all who took the time to answer.