Windows 7 Minimu size to shrink for c-partition

[hummer7]

I got a new Dell Win7 computer with 640 GB hard drive.
But free space for C-Partition in the new computer is now 555gb.
For my XP computers, the size of C-partition is about 60 GB.
So I tried to shrink 555 gb size to 60 gb in the Disk Managment.
I could not shrink to that low but only allowed to to 296 GB (285 gb for the rest of unallocated space).
I wonder why I could not shrink below 296 GB (i.e., to 60 gb).
Could someone suggest me how to go around it? Thanks. Hummer

 

[EveningStarNM]

Why do you want to shrink that partition?

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