Windows OS Partition Size Question

#1
As I mentioned in another post, I am going to be setting up a triple-boot config (XP Professional, Vista Business, Windows 7 Professional) on my new home recording PC. I was originally going to use a WD VelociRaptor 150 GB HD, and put 3 partitions on it at 50 GB for each OS. I'm now considering using the 300 GB version of this VelociRaptor HD, and utilizing its considerable speed and additional storage capacity by also installing my applications on a 4th partition on it, in addition to the 3 Windows operating systems. (Separate drives will be used for data storage and backup.)

My question now is, what are the minimum "comfortable" partition sizes to establish for each OS? I'm assuming that it will be considerably less than the 50 GB per OS that I was originally going to allocate, and I'm also assuming that the answer will be different for each OS.

So, what partition size should I use individually for XP Pro, Vista Business, and Windows 7 Pro? Remember that I am looking for optimal partition sizes that will allow ample room for each OS to run without any compromises (along with necessary system file allocations), so that I can maximize the size of the 4th partition dedicated to applications.

Thanks in advance for any input that can be given concerning my question....
 

Terry60

Knows where his towel is.
Staff member
#2
Here's my ultimate conclusion from the same question.
I originally had very tight space restrictions on all my OSs (25Gb) because I install all apps in separate partitions and keep data files in yet another, accessible to all.
I soon realized that despite my best intentions of keeping the OS static, MS had other ideas, and massive SPs and emergency Update packs had me struggling up against the limits, and generally meant my system restore facility was limited between a few hours and a day or so, tops, because of the fifo queueing and the lack of space.
At the cost of a weekend of hard work (and a HDD upgrade) I reorganized everything as you see.
(XP stays small because it's end-of-life and not subject to future SPs. I just use it for legacy app and legacy hardware support)
 
Last edited:
#3
Here's my ultimate conclusion from the same question.
I originally had very tight space restrictions on all my OSs (25Gb) because I install all apps in separate partitions and keep data files in yet another, accessible to all.
I soon realized that despite my best intentions of keeping the OS static, MS had other ideas, and massive SPs and emergency Update packs had me struggling up against the limits, and generally meant my system restore facility was limited between a few hours and a day or so, tops, because of the fifo queueing and the lack of space.
At the cost of a weekend of hard work (and a HDD upgrade) I reorganized everything as you see.
(XP stays small because it's end-of-life and not subject to future SPs. I just use it for legacy app and legacy hardware support)
Thanks for the info and the jpeg! I guess that I'm not too far off the mark then, and I'm going to use your approach as my model when setting up the hard drives and operating systems. I especially like your idea of establishing separate logical drives for each OS's apps, instead of having a mish-mash of everything piled into one partition, like I was going to do.

The only thing that I'm really puzzling over is the 16 MB "Boot (B)" partition. What is it used for, and what is the logic behind the small size? (Sorry if this is a dumb question.)

Thanks again for your assistance. It is much appreciated,
 

Terry60

Knows where his towel is.
Staff member
#4
See post #2 in this thread.
(no longer quite up to date because W7 has gone from being a Beta test single partition to my default OS and has its own apps partition J: as you've seen, not reflected in the menu.lst of this old post)
 
Last edited:
#5
Thank you for the explanation. Am I correct in my assumption the the small "Boot" partiton is unnecessary for my simpler XP > Vista > Win 7 triple-boot setup?
 

JustinW

Super Moderator
Staff member
#6
The small boot partition isn't needed but is created automatically if you install W7 to an unpartitioned space. In that case it IS what is used to boot the computer and IS important. If you want to eliminate it from the picture set W7's main partition as active, delete the boot partition, and run startup repair 2-3 times from a Windows 7 DVD to rebuild the BCD. Use [thread=642]EasyBCD latest beta build[/thread] to add an entry for XP when you get W7 booting and let it autoconfigure.
 

Terry60

Knows where his towel is.
Staff member
#7
In this case Jus he's talking about my small boot partition, nothing to do with W7.
The W7 BCD is in its own partition.
I created a separate boot partition because I wanted to use the grub "setdefault" facility which is restricted to being in the 1st partition and never being hidden.
That ruled out both Vista and W7, hence the little boot partition.
It also enabled me to keep the W7 and Vista BCDs separate and dedicated to their own OS (which prevented the back-levelling of the startup splash screen problem, subsequently fixed in EasyBCD)
Unless you have particular reason to do it, as I did, there's no need for a separate boot partition.