Well this type of issue may be hard to resolve remotely and i only have one hunch/guess left for now which is... see if you can locate a file folder entitled "symbols" and determine the size ... it is usually large and I'm only guessing that it "might?" "maybe?" help explain the 7gigs. Probably > c:\symbols
As I mentioned above I use two drives loaded with Win7 and the one I strip down for Benchmarking in which I remove the symbols files, but I don't bother doing that with my everyday use drive as I have more than enough space 250G and symbols would be necessary to run debugging process.
You can learn more about what it is and it's purpose here:
http://msdn.microsoft.com/en-us/library/windows/hardware/ff558823%28v=vs.85%29.aspx
Also re-check that your pagefile wasn't reset to a huge amount after the updates... beyond that Kamhagh ??