Black Candles are bearish lines in candlestick and candlevolume charts. They signify that the closing is lower than opening for that time period.
CHKDSK, short for Check Disk, is a utility that checks the integrity of the files and file structure of your hard disk. I'll walk you through it. I have disk problems and you said I should run CHKDSK. Great.
CrystalDiskInfo is a utility tool that can tell you about the hardware performance of your hard disk, including how likely it is to stop operating in the near future. The app gives you a complete readout of all your computer's SMART information, as well as a current temperature and health status.