SATA cables come in different colors(I personally have RED/Blue/Black/White ones).
Chances are it is a SATA cable.
As for drive speed, you may need to run some tests on the drive to ensure it is working correctly.
Please grab
CrystalDiskInfo to see if any smart attributes look out of place.
It also never hurts to run a test from the driver manufactures website(Data Life Guard for western digital/Seatools for Seagate/ect).
HDTune(you do not need the PRO version the normal one has the scan option) has a generic surface scan that works with most drives.