Empty drive is apparently not empty

[BWest]

Hello,
I am new to FreeNAS, but with the help that I have found around the web, it has been a pleasure to work with. However, there is this one thing that is bugging me. I am using an old craptop as the base and then I'll be adding external hard drives for the majority of my NAS. However, I haven't gotten that far yet because I've been fighting with the laptop's primary 320GB HHD. When I first booted into FreeNAS and added the drive, it told me that it had 268.1 of 291.4GB free. I Figured that it was due to the Ubuntu I had on it before so I tried wiping the disk with FreeNAS (Quick, full with zeros, and full with random). That didn't work. I tried taking the disk out and hooking it up to my main computer and destroying all the partitions and formatting it fresh. That didn't work. In desperation, I even used dd on it. Still no luck. There is no way there should be any data left on this drive, but still it says 268.1 of 291.4GB. I've run out of ideas and was hoping someone here as some.

 

[BWest]

Well, I tried again. This time I coupled a fresh re-formating of the drive in my other computer with a fresh FreeNAS image on my flashdrive. Same old, same old.
First image is the disk after formating it on my main computer. The second is FreeNAS telling my that the empty drive is not empty.
If anyone has any ideas, please let me know. This glitch or whatever it is is driving me nuts!

 

[BWest]

Back with another crazy idea that didn't work. I tried an other old drive, a 120GB HHD. I plugged this one in and it reads just like the first. Even though it has been formated fresh, FreeNAS still thinks that there is some data on it. In this case, it is 99.4 free out of 108.1 (in both cases, about 8% of the available space is listed as in use when it isn't).

Please, Can anyone on this board offer any insight as to why this thing is giving me so much crap?!?

 

[paleoN]

(in both cases, about 8% of the available space is listed as in use when it isn't).

I take it you are using UFS. It's normal.

 

[BWest]

Thanks.
Well, that is frustrating. I tried researching the "Why" and had no luck. Is it somewhere on http://doc.freenas.org/index.php/Volumes and I just missed it or is it the sort of thing that only comes with knowledge/experience?