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I have win7 installed on my main drive (450~ GB). Is it possible to split it without ruining the HDD?

Right now I'm running Computer Management to actually do the deed, but some things seem weird.


267 MB of free space? Seriously? I have 188 GB of free space and was considering a new volume of 110GB.

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Why could this be happening?

I've never split a drive before, so I need all the help I can get. If I successfully split my drive and install win8 on the new volume, will I be able to use my PC with two different operating systems?

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Have you actually tried defraging your drive? I believe Win 7 automatically schedules it every week, but Computer Management will only shrink your volume to the furthest sector a file resides on. You might want to consider other tools is Diskpart or something. – hydroparadise Jan 3 '13 at 22:04
"Computer Management will only shrink your volume to the furthest sector a file resides on" - Yeah, as the dialog clearly indicates. – Karan Jan 3 '13 at 22:06

267 MB of free space? Seriously?

No, 267 MB of free space at the end of the volume. Not 267 MB total free space.

Imagine your C: volume like this:

Where the U mean in use, and the F means free.

Now look to the end of the drive. It has two F's. You can shrink it by those two. Even though there are a lot more Fs elsewhere on the drive.

What you probably want to do is to find a way to move all used sectors to the beginning of the drive. Defrag might do that.

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Use a better partitioning program (that will take care of moving the data for you) such as GParted, or if you want to do it within Windows itself download something like EaseUS Partition Master Home Edition. Use that to shrink the system partition, then boot from the Win8 installer media, create a new partition in the unallocated space and install as usual. The Win8 bootloader will take over and allow you to dual boot.

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So if I'm going to install win8 on the new volume I have to leave it unallocated and run win8 installer right afterwards? – Vera Jan 3 '13 at 22:15
Yeah, or you can create a new partition from the partitioning program itself and just select that in Win8 setup. Any way will work. As for "right afterwards", take your time, the unallocated space is not gonna disappear! :) – Karan Jan 3 '13 at 22:18
I am using EaseUS right now, and it's asking me if I want a primary or a logical drive. Which one is better suited for an OS? – Vera Jan 3 '13 at 22:27
If it allows you (depending on whether you are using MBR or GPT, and how many primary partitions you have already), create a primary partition. Remember to click Apply to complete all Pending Operations (some of which might require a reboot, and you should ensure proper power supply during the process). – Karan Jan 3 '13 at 22:28
+1 for recommending EaseUS. – trpt4him Jan 4 '13 at 0:25

I encountered this exact situation, as in not being able to free up enough hard drive space for the Windows 8 partition. What I needed to do was temporarily move or disable my hiberfil.sys and pagefile.sys files. I assume the drive could not be shrunk beyond where these files were located on the drive. What I did was shrink the C drive as much as allowed, create a new D drive using the default amount of space, temporarily change the location of the pagefile to the D drive. temporarily disable hibernation (this deletes hiberfil.sys), then reboot the computer. After rebooting I was able to further shrink my C drive and make my D drive larger for the Windows 8 install. Finally I restored the pagefile location to my C drive and reinabled hibernation. I now have Windows 7 on C and Windows 8 on D. Dual boot works just fine. FYI, I use EasyBCD by NeoSmart to manage my dual boot options. Works well. Don't think I missed any steps here.

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You should try to defragment your drive using Defraggler boot time option.

If that does not help you to recover more space for shrinking, there is one method that will definitely help: use PartedMagic.

Easiest way to get started with PartedMagic is to create bootable USB stick using Unetbootin, which has an option to automatically download PartedMagic and make your USB stick bootable with it.

Then, boot from PartedMagic USB stick and use GParted to resize your C: partition down to desired size.

Alternatively, you can install UBCD, which also has PartedMagic option among other very useful options.

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