How much spare space does Windows 7 need?

That's very tough to answer, as it would change system to system, but why not step into a modern solution? Do away with the old, out-dated multi-boot systems, and virtualize. I run an SSD for my OS/apps drive, and store several VMs on my larger spinner. I get near native speeds, without messing with bootloaders. It's a much simpler setup than multi-booting, and I can run quite a few various OSes.

DMHolt57 said:

80GB works out well, about 12-16 for the OS and 60 or so for overhead/apps

Thanks, but I am not asking for total. I know exactly what space the assigned files use now. And this space (system, apps, app data, user/app files, etc) is different on each installation. For example one has all the daily stuff. Another has only a single video NLE, because it does not play well with others. The first is twice the size of the second.

DeaconFrost said:

as it would change system to system,.

Yes but surely not wildly. I'd guess 5 is too little, 50 more than enough. Can anyone narrow that?

DeaconFrost said:

but why not step into a modern solution? Do away with the old, out-dated multi-boot systems, and virtualize... It's a much simpler setup than multi-booting, and I can run quite a few various OSes

I'll have to research this. But my purpose is not to run different O/S.
It is to run certain apps (video NLE) on the same O/S, but on an isolated and "clean" installation, as recommended by the company. As I understand it this avoids codec confusion as well as interference from background tasks.

gregglee said:

Yes but surely not wildly. I'd guess 5 is too little, 50 more than enough.

Yes, it can, actually. It depends on the apps you use, how much caching space they need, how big the drive is, how much memory you have, etc. There are plenty of factors that go into it. Look at your current system volume and how much space that takes up. Are you planning to install any apps on spinner drives instead of the SSD? if so, subtract the size of that app. Then you'll know how big of an SSD you'll need. On my work laptop, I can get away with a 64 GB drive, and have 30-40 GB free. On my tower system in my specs, I am using a 128 GB drive (will be very soon). It all changes from computer to computer, and no one else can really give a good answer to this besides you.

As for the apps, there has to be a better way than paying for multiple licenses of the same OS.

DeaconFrost said:

That's very tough to answer, as it would change system to system, but why not step into a modern solution? Do away with the old, out-dated multi-boot systems, and virtualize. I run an SSD for my OS/apps drive, and store several VMs on my larger spinner. I get near native speeds, without messing with bootloaders. It's a much simpler setup than multi-booting, and I can run quite a few various OSes.

Wouldn't virtualizing mess with the hardware compatibility? I'd probably opt for a dual boot so that the OS can use every resource possible.

VMs are designed to be extremely compatible. They typically don't even need drivers loaded, aside from the respective VM tools. They also have native and direct access to the host's hardware.

DeaconFrost said:

VMs are designed to be extremely compatible. They typically don't even need drivers loaded, aside from the respective VM tools. They also have native and direct access to the host's hardware.

My bad, I was thinking Windows Virtual PC, which is a fail all on it's own. VMware on the other hand is quite good.

It is, but it is also expensive. Virtualbox is completely free, and works very well.