PCIe 4 drives will run, but at PCIe 3 speeds -- the system does not have PCIe 4 support. You have one M.2 drive slot and if you have the smaller 4-cell battery, a 2.5" SATA bay.  If you have a 6 cell battery, you have only the M.2 slot. Only you can decide whether you need more RAM;  for most applications, 16G is plenty.
Hello, I would like to upgrade both my ssd and hdd .   does the laptop support the 2280 gen 4  ssd's ?  something like this   a) "[URL]" b) does the laptop have another ssd slot? as i wish to replace the hdd one,if no 2nd ssd slot is available  ... which high capacity hdd  8tb+ harddisk do you recommend?   my Ram memory is @ 16gb , should i upgrade it to double that size?
G7 7790 ssd ,hdd upgrade , does the laptop support g4 ssd's ?