Harddrive 11 Gigs smaller?

Ok, so i have an E-machines T5082, i upgraded the Ram, put a better Graphics card in it, the like

A few years ago after tinkering around with some weird stuff that i didn't understand, my drive got smaller. After looking around i learned that i had partitioned it or the like, so i deleted the partition and the drive went back to normal. A virus later took hold and the partition thing happened again.

Long story short, for some reason, i am missing 11 Gigs from my HDD, and i KNOW its not Windows Vista taking 11 gigs. I mean, in My Computer, its reading my HDD as 149 GB instead of 160 like it USED TO. How can I get back these 11 gigs, WITHOUT reformatting or anything like that?

im sure that's normal mate, you never get the retail amount of HDD space reported b/c of the way the bytes are calculated (im sure someone here has the full answer).....

check out my 2x 160GB HDDs..... both reporting 149GB

In additiuon to Skunks comment above and just to rule out a 'mysterious' partition, could you post a screenshot of your 'Disk Management'

(Right-click: Computer > Manage > Storage > Disk Management)

Example:

Chart Courtesy of Western Digital.

Well thats strange. since it always used to read as 160 Gigs, like when i first got it.

But on my second drive i have 9MB of unallocated space.. Gonna try to allocate it XD