Info Inspiron 15 3xxx i5-7200 is extremely slow

[RobertNelson]

I changed hdd to Ssd , 4gb ram to 12 gb ram , checked background running apps and services, cpu only at 5% not clogged at 99% but still 100 seconds to boot and 25 seconds to load apps.
! SOLVED: THE FIX ! :changed ram to Ddr4–2133 MHz from Ddr4–2400MHz. Ddr4–3200MHz also increcredibly even slower. Apparently Inspiron 15–3xxx can only run fast on the slowest DDR4 ram , maybe call it Unspiron?
If you want a faster Inspiron 15 with DDR4 ram get DDR4–2133MHz aka 17000 , now its faster !