Solved C: drive losing memory

Hi all, it's my first time here and I have a question about my C drive.

I started noticing about a week ago that I was slowly losing memory in my C drive without me using it. In other words, it is disappearing. I have seen this before on several windows 7 computers, but I don't know how to solve this problem when I'm running windows 8. (I'm running it on a 128 GB SSD HP spectre.) A few days ago I had 4.79 GB free. Yesterday I had 4.67 GB free. This morning I have 4.66 GB free. All this while I have not saved anything onto my computer, installed any updates, etc.

Furthermore, when I purchased this computer a year ago, it already came with about 70% of the C drive used up. I assumed it was bloatware that was taking up the space and have since given up on removing it, but I'm growing suspicious that it has something to do with the disappearing memory.

Many thanks to any help!

edit: Sorry in advance if this is posted in the wrong forum; I couldn't decide between Drivers & Hardware and General Support...

Welcome to the forum,looks like you are not deleting any of your temporary files that are saved in the Windows temp folder.Download CCleaner,one of the most trusted temp files cleaner (and many,many things more),set it up according to your needs and you should be just fine.Do ask for any help needed,everybody is willing to give a helping hand,keep chewing your food...

Thanks, proudtobegreek. That freed up quite a bit of space (around 7 GB). But I'm still confused about where the rest of the space on my C drive has gone. My desktop files only occupy 12 GB of space, and the only space-taking programs I've installed are MATLAB, Photoshop, and Microsoft Office. What, then, occupies the rest of my C drive?

Look into the System Restore points and delete the ones you don't need or restrict their total size.

Try running one of the free disk usage utilities (I use Treesize Free but there are others) as administrator, and it should show most of it.

Hibernation takes up a Gig(if enabled),pagefile and swapfile could be another two or so,windows updates cache are taking up some space,AV stores its updates also,each and every system restore point could be about 200MB, Superfetch feature-service does keep things writing and storing,Windows events and even memory dump files are to "blame".Scheduled Windows Back-ups?No worries,you are at the right place,tutorials and members will give you the helping hand for every single issue.