CPU UPGRADE HP EliteBook 8560w Workstation.

[AAM9]

DEVICE HP EliteBook 8560w Workstation.

CPU CORE I5 2nd GENERATION

RAM 16GB

HARD HDD500 + SDD128

VIGA CARD 2GB NVIDIA 

I want to upgrade my note book CPU it is EliteBook 8560w Workstation.

it is Core i5 2nd generation. which bothers me a lot as it goes up to 100% while using and the device freeze for some seconds then it work again.

i tried disable start up programs,... but ehwn i use browser with 15 tabs open + youtube + google drive it freezes for som time

SO my thinking is if i upgrade CPU to newer generation i will serve me better and cost me less from buying another laptop.

PLEASE advice me what i should do and which CPU i need to choose with zero problems in the future?

WHERE i can buy CPU online?

PS: if some one walked this road before with the same device PLEASE share your experiences.

i found out the combatable CPU from the user Manuel page 90 which is 

i7-2860QM, 2.50-GHz (Turbo up to 3.60) processor 8-MB L3 cache, 8 threads 666175-002
i7-2820QM, 2.30-GHz (Turbo up to 3.40) processor 8-MB L3 cache, 8 threads 657414-001
i7-2760QM, 2.40-GHz (Turbo up to 3.50) processor 6-MB L3 cache, 8 threads 666174-002
i7-2720QM, 2.20-GHz (Turbo up to 3.30) processor 6-MB L3 cache, 8 threads 657413-001
i7-2670QM, 2.20-GHz (Turbo up to 3.10) processor 6-MB L3 cache, 8 threads (not configurable
with iAMT)
665116-002
i7-2630QM, 2.00-GHz (Turbo up to 2.90) processor 6-MB L3 cache, 8 threads (not configurable
with iAMT)
657412-001
Intel Core i7 processor, dual-core
i7-2640M, 2.80-GHz (Turbo up to 3.40) processor 3-MB L3 cache, 8 threads 666173-002
i7-2620M, 2.70-GHz (Turbo up to 3.40) processor 4-MB L3 cache, 4 threads 657411-001
Intel Core i5 processors, dual-core
i5-2540M, 2.60-GHz (Turbo up to 3.30) processor 3-MB L3 cache, 4 threads 657410-001
i5-2520M, 2.50-GHz (Turbo up to 3.20) processor 3-MB L3 cache, 4 threads 657409-001

mother board