Your laptop has two slots that can accommodate a total of 16 GB RAM (two x 8 GB), DDR3L-1600 SODIMM. More RAM will allow you to have more things loaded in RAM at once, and can speed up some operations as it reduces disk-to-RAM swapping. You didn't say whether it has a hard drive or an SSD. If it's a hard drive, replacing it with an SSD will make it much faster and more responsive, a noticeable difference. I recently bought a Crucial Mx500 1TB SSD for about $100 Canadian. And, you may not even need that much storage. Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. I know many people do such work without this, but it's a cheap and sensible precaution.
With the last update through Windows my laptop runs very slow and most of the time can't open icons or downloaded forms. When I click Ctrl and Alt and delete, too see how much memory I am using it say 74% Can I upgrade the memory. You know put in new one. How much can I add ? That would make my laptop run faster like it used to.   Please help
I have a Latitude E5540 laptop that was upgraded to Windows 10 64 bit.