How can I combine two identical harddrives?

OS is Vista. I could not find the edit function to add this to my original post.

We need to know what you mean by "combine".  What is your objective?  The things you can do having two identical disks are 1) clone the existing disk to the second disk to make a spare, 2)  depending on the computer, you can usually create a RAID 1 or sometimes a RAID 0, 3)  Essentially make the second disk your data file by copying all data from the first disk to the second, deleting the data from the first disk to leave it as your system disk.

Incidentally; on the subject of RAID, RAID 1 does not increase your storage as it simply mirrors the first disk on the second, which is then used as a "hot spare".  RAID 0 is fun as it creates a volume having twice the size of one of the disks and speeds data transfer by about 20% to 30%, but is not recommended unless you also have a good plan of backing up your data.  Failure of one RAID 0 disk loses all the data stored to the volume which cannot then be recovered.

P.S. The edit function is reached by clicking the pencil icon at the lower left of your post.

JackShack, Please bear with me as this is a new area for me. I am restoring a laptop for use in a senior center.  I have already used the hidden restore partion on this laptop. I did not have any discs for doing a clean install. I noticed that there were two drives listed, C which had the OS and programs, and another drive D (also labeled data) which had nothing on it. There was a third drive which contained the restore to factory program.  Drive C and D are the same in size.What I would like to do is make this one large voume rather than the two smaller ones without losing the new restore, OS, programs, etc. From your explanation it seems like I need instructions for raid 0.  I do have another external disk for backups. Is it possible to do this?  The OS system is VISTA.

Ahh-I found the pencil. Thanks for that tip.

Since we are discussing a laptop you most likely do not have two physical disks, but rather two partitions on the same disk.  You can't make a RAID unless you have two actual hard drives.  Was the laptop shipped by the manufacturer in this configuration?  Dell was shipping laptops with a similar configurationn for a while.  The C drive would be 60 GB or so, leaving the remainder of the disk with an empty D partition.

In order to reconfigure the drive to a single C partition you must use Disk Manager to delete the empty partition, followed by using the built-in partition editor in Vista to expand the C partition to occupy the resulting unallocated space.  You should make certain that you have updated Vista to the most recent service pack as the original release had some problems with the built-in partition editor.

hi:emotion-1:

One way that i  know to combine two drives is, first delete one drive ( as soon as you delete one drive the space will be made unallocated) then extend the another drive to the size of unallocated space. In your case, you can delete D drive then later you can extend C drive. 

But when you delete D drive, you will lose all the data from it (as you have no data on D, its well and good)  and i am not sure about the data security of C drive during extending it. But i suggest you to use partition recovery software, like the one i know is Remo Recover software in case you lose  your programs or other data while resizing. 

You can download the free demo version of this tool. Hope you can successfully combine your drives....:emotion-1:

I have used Disc Management and right clicked on Drive D and clicked on "delete volume."  Drive D then became unallocated space. When I right clidk on Drive C and try to select Extend Volume to merge the unallocated space into drive C I cannot click on "Extend Volume" becaues it is greyed out.  I need help.