HDDs shall at least have 7.200 rpm for editing full HD footage. Best thing about adding a SSD to run windows and apps on. A recommendation might here be the Samsung SSD 850 Pro with 128 GB. Have the other discs set up for Media and Cache/Preview.
You must be way more descriptive regarding the model numbers on your drives, especially the SSDs. There is such a WIDE range of performance depending on vintage, manufacturer, model, and size.
ok, the internals Im using now i can't get in to see the model numbers, but for the others they are;
C: OS & programs, Samsung 840 EVO
D: Media Cache & previews, Kingston SSDNow
E: Projects, 1 TB HDD
F: Media, 2 TB Seagate Constellation
G: Exports, 300 GB HDD.