A lot of people have been running the Skyrim HD mod over the Hi Res pack as the mod doesn't cover 100% of skyrim. You cannot do this without a little file modification, however.
How to use the new Official Hi-Res texture pack with user created mods:
1. Disable or delete the esps that came with the official texture pack.
2. Backup then open
SteamAppsCommonSkyrimSkyrim_default.ini
&
DocumentsMy GamesSkyrimSkyrim.ini
3. Change this in both files:
[Archive]
sResourceArchiveList=Skyrim - Misc.bsa, Skyrim - Shaders.bsa, Skyrim - Textures.bsa, Skyrim - Interface.bsa, Skyrim - Animations.bsa, Skyrim - Meshes.bsa, Skyrim - Sounds.bsa
To this:
[Archive]
sResourceArchiveList=Skyrim - Misc.bsa, Skyrim - Shaders.bsa, Skyrim - Textures.bsa, Skyrim - Interface.bsa, Skyrim - Animations.bsa, Skyrim - Meshes.bsa, Skyrim - Sounds.bsa, HighResTexturePack01.bsa, HighResTexturePack02.bsa
4. Save both files.
Source:
http://forums.nexusmods.com/index.php?/topic/554730-the-creation-kit-is-live/page__st__320