I've used Eraser in the past, and recently became aware of the cipher command in Windows 8. Specifically, with the /w flag:
/w removes data from portions of the volume it can access and have not been allocated to files or directories. It does not lock the drive, so other programs can obtain space on the drive, which cipher cannot erase. Because this option writes to a large portion of the hard volume, it might take a long time to complete and should only be used when necessary.
When running it, I see it taking 20 minutes to write 0x00, another 20 writing 0xFF, then a good deal longer writing random numbers (all via the command prompt).
I'm a little confused as I've read conflicting information as to whether or not these "eraser" type methods are needed anymore with TRIM-enabled SSDs (which I'm guessing mine is).
Basically I'm deleting a bunch of old data before a laptop gets sent to the charity bin, and just wanted to do it the best way possible since I have no idea who's using it next.
I considered using dban, but right off the bat it says:
No guarantee of data removal (e.g. DBAN does not detect or securely erase SSDs)
I've looked at some other answers, but they seem ~3 years old and I know things might have changed in that time.