Upgrade Processor from i3 to i5

Find out the model of your motherboard.
Type the model series on Google and go to Motherboard's manufacturer official website.
Find the QVL list for the motherboard.
Look inside the QVL list, it will show you all the CPUs it supports (if yours isn't listed, then it will not support it). You will see until which generation it will support.
 
That's a laptop. CPU can be upgraded. But - to 2nd gen only. May be also 3rd gen with BIOS update.
6th gen - no not possible.

Also you have to find TDP of your current cpu. Cooling solution of your laptop may not be able to support upgrade to cpu with higher TDP than current cpu.

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