170 gb unallocated HDD Space

no wipe. just do it.

No, it won't. Just curious, why are those parts unallocated, though?

You should be able to just extend your current partition to make use of it.

you can expand your other partition so you don't have 2 + partition on the same drive but having 5846 partitions or 2 partitions, is the same drive so you dont loose any performance (actually i never tried 5846 partition but its might not be a good idea after all :S )

Either extend your current partition or make a new partition. Its basically space that hasn't been partitioned yet.

try MiniTool Partition Wizard.

Okay. Now it wont let me add a new steam library folder. THere always has to be a catch.

If you use mini tool partion magic, you can actually allocate that space to your main partition or create a separate like normal. There are loads of other software solutions you can use, I just happen to have used partion magic.

EaseUS Partition Master (free). Merge the space/resize, hit Apply and restart. Easy peasy.

Or just format the partition to something usable (fat32, ntfs). It's all pretty straight forward.