X25-M G2 SSD Filled up with some hidden data then cleared?

[idata]

Today I happened to notice my X25-M G2 fill up with some hidden data then after it was almost completely full it cleared? I watched in "My Computer" as the free space available on the C drive of my SSD kept dropping by the minute. I've never ran the Intel toolbox or even had it open. From my understanding an optimize tool will fill up the drive to almost full then clear. Is that what happened here with me running Win 7 64bit and my SSD is on firmware 02HD?

After the SSD was almost completely full it cleared and my free space is back to normal and not changing. My space used on the SSD had stayed constant through the whole thing as well, 39.7 GB used (when I would highlight all files/folders in root of C and choose properties, and I have it set to show all files & system files). But when I right click on the C drive SSD and choose properties it shows used space of about 50 GB, and I can't figure out where this mysterious 10GB is?

I thought at first I must have a virus but all my scans keep coming up clean.

I just downloaded the new Intel toolbox and will try an optimize in it.

Anyone else notice this happening?

[idata]

One thing I forgot to mention that I think is probably doing this is I have Diskeeper 2010 Pro with HyperFast installed. And the HyperFast feature is an SSD auto optimizer.... so I'm willing to bet that's what I was seeing going on and just happened to notice it this one time. That makes sense. I haven't been able in the past to find out exactly how the Hyperfast works but I'm willing to bet it acts just like the other SSD optimizers where it fills the drive then clears it.

[idata]

When I run WinDirStat on my C: SSD I get 18.6GB taking up "Unknown" space. Anyone have an idea how I can figure out what this unknown space is?

When I uncheck show unknown space in WinDirStat it show me the same amount of space used as when I highlight all files/folders and do properties, 39.1 GB used.

But haven't been able to figure out this mystrious 18.6GB taking up space.

[idata]

I found what the "unknown" data is now. It's my "System Volume Information" folder for restore points. I didn't have permission to view it then and now I do and that's where my missing used up space is.