1. If it isn't in the user manual, I'd ask Dell customer support what CPU's are compatible with the motherboard, and if - for the one you buy - a BIOS update is needed.
2. http://www.crucial.com/usa/en/compatible-upgrade-for/Dell/inspiron-1720 says max 4 GB of RAM.
It might be better to buy a new laptop.
Kees
Hi,
I would like to upgrade the processor on my Dell Inspiron 1720. Currently I have a Intel (R) Core (TM)2 Duo CPU T7100 @ 1.80 GHz. My Motherboard is part number WK802. I want to upgrade the processor to 2.5 GHz or higher if I can. I want to be able to upgrade to Windows 8.1 64 bit OS. I already upgraded the RAM to 4GB. The OS is Windows Vista 32 bit. I also want to be able to upgrade the RAM to 8GB once the OS is upgraded. Is it possible to do this with this machine?

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