Windows Image sizes continue to get bigger and bigger. I recently recreated my WIMs that I use for testing and applied all important updates through March of 2015 before taking the capture (using MDT of course). For Windows 7 (both 32-bit and 64-bit), I started with the latest available Windows 7 Enterprise with SP1 ISOs. For Windows 8 (both 32-bit and 64-bit), I started with the latest available Windows 8.1 Enterprise with Update (released in December 2014).
Prior to the capture, I ran the Disk Cleanup utility to remove any unnecessary files and reduce the size of the final captures. Below is the end result with a comparison of the original ISO sizes.
|OS||WIM Size||ISO Size|
|Windows 7 ENT SP1 x86||3.29 GB||2.26 GB|
|Windows 7 ENT SP1 x64||4.93 GB||2.96 GB|
|Windows 8.1 ENT with Update x86||2.93 GB||2.84 GB|
|Windows 8.1 ENT with Update x64||3.86 GB||3.85 GB|