Will this fit?

[jazon1]

I run Windows 7 x64 Ultimate + Office + a few other programs, and I'm using about 25GB of space.

The biggest space user of anything is games, btw. My Steam folder takes up more space than almost all my other programs combined.

true but his install will be at least 6 gigs larger than yours.
the operating system will create a page file that is one and a half times the amount of RAM, hes getting 8 gigs so his page file will be 12 gigs on c: drive unless he shrinks it or puts it on another drive.

 

[Knufire]

true but his install will be at least 6 gigs larger than yours.
the operating system will create a page file that is one and a half times the amount of RAM, hes getting 8 gigs so his page file will be 12 gigs on c: drive unless he shrinks it or puts it on another drive.

A good amount of people either disable page file or move it to the HDD with a solid state to reduce the amount of necessary writes and/or free up more space on the SSD.

The page file (as I'm sure you're aware, but the OP may not be) is where the OS stores information that would have been on the RAM in case your RAM usage is 100%. With the ridiculous amounts of RAM we're putting into our system nowadays, that will almost never happen. I've never seen RAM usage about 67% (4GB) on my machine, ever. It's relatively safe to move it to the HDD without worries.

There are several easy tweaks (such as the page file) that you can use to get a Windows installation size down.

 

[jazon1]

yea page file is mostly useless if you have alot of ram,i was assuming the OP is a bit new to custom builds and wouldn't be messing with his OS for awhile so i aired on the safe side for a SSD size suggestion=) im sure my own installation is so large now from my 3dsmax and photo editing programs.

 

[Knufire]

The whole debate is a bit pointless anyway, since there isn't any reason NOT to get a 120GB drive, which you could fit almost your entire Program Files folder on as well as Windows.