SOLVED
Alrighty, for any future OVH customers...
When you choose to install (or re-install) your Dedicated Server, follow these steps.
- Select Reinstall from your manager
- Choose the distro you want (Debian, Ubuntu, etc)
- Click Next
- In the bottom left is a checkbox "Use Original Kernel"
- Select this, then hit "Next"
- Compile as normal
Pro tip: Don't skip over selection boxes when they involve your server.