Upgradation of more than 8GB RAM & Nitherboard

Welcome to the Dell Community @Ameya1 

Yes you can upgrade to 16Gb memory.

Memory
Slots Two SODIMM slots
Type Dual-channel DDR3L
Speed 1600 MHz
Configurations supported 4 GB, 6 GB, 8 GB, 12 GB, and 16 GB

Inspiron 14 5447 Specifications:

https://downloads.dell.com/manuals/all-products/esuprt_laptop/esuprt_inspiron_laptop/inspiron-14-5447-laptop_reference%20guide_en-us.pdf

Yes you can upgrade to a 3 or 4 TB SSD.$$$

Dell Inspiron 15 (3543) Motherboards:

https://www.parts-people.com/index.php?action=category&id=141&subid=510&refine=motherboard

Best regards,

U2

To upgrade the CPU, you will need to replace the entire system board, yes.

Sorry @Ameya1 

I was working one two other posts and pasted the wrong specs.

8GB is the max.

Memory
Slot One SODIMM slot
Type DDR3L
Speed Up to 1600 MHz
Configurations supported 2 GB, 4 GB, and 8 GB

https://downloads.dell.com/manuals/all-products/esuprt_laptop/esuprt_inspiron_laptop/inspiron-15-3543-laptop_reference%20guide_en-us.pdf

The motherboards are correct.

https://www.parts-people.com/index.php?action=category&id=141&subid=510&refine=motherboard

Sorry for any inconvenience,

U2

Thanks for the details, I need to upgrade for Inspiron 3543. You have mentioned Inspiron 5447 which is not applicable for my laptop. I checked the website as well, they are only supporting in USA. I'm from India & if I order from there it will cost more than what is purchase including taxes & all details. If there's such site for India as well it will be great.

As planning to upgrade my lapy with more than the current one. 

Ohkay then only 8GB RAM & 2TB is SSD is max. Support. Any local site that supports within India? 

Yes planning of that

@Ameya1 

3TB or 4TB will still work in just about every laptop made with a SATA or M.2 interface.

Regards,

U2

@Ameya1 

Dell manuals are good for referring to what was sold with the laptop.

They are not referring to the limitation of the hardware.

Regards,

U2