I am not sure if its relevant here after all this time, but just wanted to mention. I have the NP365E5C-S02UB running Windows 8.1 x64 ... and its Synaptics Drivers also weren't working. So ...
- I used Samsung's software "SWUpdate" & searched my Laptop manually by choosing Win7 as the OS (Win8.1 would only show TWO updates, AMD Catalyst & Bluetooth Drivers)
- Chose the "Touchpad Driver" (saved on my HDD) and it came out as "Synaptics Touchpad Driver_16.2.1.1".
Previously i tried downloading the latest Synaptics from their official website *synaptics.com" but the latest version v17.0.19 didn't work)
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That being said, my Functional Keys are also not working. I might find a Win7 driver which could help me enable those keys (none of the functional keys are working), and i'll definitely post here if i find anything.
Just mentioning it here, if it helps anyone
Thanks for reading
EDIT: A little update. I downloaded & used Win8's Synaptics Touchpad Drivers (from SWUpdate) which were v16.2.2 (later than the Win7's version) and it fixed my "Laggy pointer" problem and also brought back some missing features from the touchpad (it was missing multi-touch on previous Win7 Drivers).
Still haven't been able to find any drivers which would make my "Functional Keys" work again :S