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My HP computer has 1 hard drive, and 1 partition has the Windows Vista on it. One other partition is also a primary partition, which has the Recovery Data on it.

It is said that a hard drive can only have 4 primary partitions? In that case, can 3 other OS'es be installed on the computer? I hope to install:

  1. XP
  2. Windows 7 32-bit
  3. Windows 7 64-bit

It looks like 3 more primary partitions are needed -- is there a way around it? .


can you install Windows 7, Windows 7 64-bit, XP, etc, on extended partition? I used the Disk Management tool on Windows 7 and it won't initialize the 5th partition, saying it is too many, so how can it be made into extended?

also, a reason I wanted to install multiple OS'es is to see how fast programs run on them natively.

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up vote 2 down vote accepted

You can only have 4 primary, but you can have as many extended partitions as you want (well, up to 26 before you may start have problems in an everyday computer example).

This shouldn't be a problem, but frankly, I wouldn't... you will just be looking for more trouble than it's worth.

If I was you, and your PC is of reasonable power, install Windows 7 64 bit or XP and then install Virtual PC or another virtualisation software and run it that way.

I can understand situations where you will want to have separate OS's, and I used to do it all the time (the more the better!) but I personally just don't think it's worth doing unless you have a real specific reason for it.

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thanks. please see the "Updated" portion in the original question – 太極者無極而生 Oct 22 '09 at 18:59
It is not always easy to convert, if this is something new and you do not have anything on them, I would just delete then create new and create it as extended. – William Hilsum Oct 22 '09 at 19:05
The extended partition is essentially just a placeholder for the extra logical partitions (ie it does not get formatted and allocated a drive letter etc)and counts as one of the four primary partitions that you are allowed. Have a look at the diagram here: – Neal Oct 23 '09 at 2:36

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