For Windows 8.1 specifically, patched ISOs are attractive because Microsoft stopped official support. But tread carefully.
If you are looking for official updates to "patch" a standard installation, Microsoft provides them directly:
81 Patched - Getmyos Windows
For Windows 8.1 specifically, patched ISOs are attractive because Microsoft stopped official support. But tread carefully.
If you are looking for official updates to "patch" a standard installation, Microsoft provides them directly: getmyos windows 81 patched