How much free space to leave on hard drive?

[Tech71]

(11-20-2016, 01:28 PM)Britec Wrote:  5% to 10% is as low as you should go, its not good to run the hard drive at full capacity, it will become slow and fragmented, so the less space you have, the more fragmented your hard drive will become and you or Windows will not be able to defrag the drive anymore. Which is not healthy for the hard drive. Solid State Drives (SSD) might be a different story altogether. 

This is not good:

Image Source

Here is a nice article:
Why Does Emptying Disk Space Speed Up Computers?

Are you mainly talking about the system drive? How full is too full with external drives? I am mainly talking about HDD's but am also curious about SSD's

[Compton]

it should be the same if you using a hard drive for storage

[Partha]

(11-20-2016, 06:47 PM)Tech71 Wrote:  Are you mainly talking about the system drive? How full is too full with external drives? I am mainly talking about HDD's but am also curious about SSD's

It doesn't matter if it's a system drive or any other drive. Based on the clutter and the space available, Windows determines if the drive requires a defrag or not

Solid state drives are built differently and they are optimized in a different manner.