So you are looking for a low budget laptop that has 4 memory slots and an m.2. m key slot to support NVME drive.
That would be none.
Only new 2016/2017 high end laptops will even have an m2 slot that can take NVME drives like the 960.
I am astonished that any laptop had 4 upgrade slots, just having 2 sockets is amazing for today's systems.
Anything that is not an ultraportable will be able to take a 2.5" drive.
Also FYI, it helps to state an actual dollar amount for "low budget" as for one person low budget means $200 and for another it means <$1000.
I would suggest searching for what laptops support the 960, then just see if you get lucky on it having 4 ram slots.