SKHynix Gold P31 (the best for me) or Samsung 970 Evo Plus

https://www.amazon.com/dp/B08DKB5LWY?th=1&psc=1

https://www.amazon.com/Samsung-970-EVO-Plus-MZ-V7S2T0B/dp/B07MFZXR1B/ref=mp_s_a_1_3?crid=ETGCANUXJMYV&keywords=970+evo+plus+2tb&qid=1672343303&sprefix=970%2Caps%2C500&sr=8-3

I still recommend the undervolting because this laptop gets hot when playing games . The LP4 is no longer used as a gaming laptop though. So it's been a while since I've explored anything with it. Below is the NVME that I replaced the BiWin SSD. Not really the cheapest anymore but it was when I first got the LP4

SK Hynix Gold P31 1TB PCIe NVME Gen3 M.2 2280 Internal SSD

https://www.amazon.com/gp/product/B08DKB5LWY/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

I just installed this bad boy and I love it so far.

I simply added a new SSD to the open slot and left the OEM SSD alone. I got a 1 tb SK Hynix Gold P31 because it was fast, cheap, and I saw it recommended for laptops because of its power efficiency.

I'm pretty sure 980 pros will be great since I think they are pretty much the gold standard for nvme ssds. I personally didn't go for them because of price and I heard they run hotter and use more power, however I have never owned one so I could be wrong.

When I finished installing my SSD, I formatted the old drive and did a clean install on my new SSD. If you do clean install, don't forget to download all the necessary drivers and software from the dell website. I got Dell Updates (can also be used to download drivers), Dell Power Manager, and Dell PremierColor and everything has been working great for me.

If you already have stuff installed or don't want to go through all the trouble, cloning should be fine. I cloned my windows install to a nvme on my desktop and nothing wrong happened. I'm pretty sure Samsung ssds come with/can use a software called Samsung Magician, which I heard good things about and I think can be used to clone drives.

SK Hynix Gold P31 would be a good choice too.

Your laptop only support up to Gen3, so buying a Gen4 would be a little waste unless you plan to re-use it in your future upgrade.

I just did a clean install 2wks ago... running 64GB ram

Crucial 64GB Kit (32GBx2) DDR4 2666 MT/S CL19 SODIMM 260-Pin Memory - CT2K32G4SFD8266

https://www.amazon.com/gp/product/B07ZLCC6J8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Added a faster NVMe Drive (3,500/3,200mb/s r/w)

SK hynix Gold P31 1TB PCIe NVMe Gen3 M.2 2280 Internal SSD - up to 3500MB/s

https://www.amazon.com/gp/product/B08DKB5LWY/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

also threw an old 1TB Crucial MX500 into the 2.5 slot...

all worked great and booted right up