So im planning on getting rid of my isp router with a mirco atx system with a adsl card with some extra nics to . I would like to have a beefy system to run proxmox on so i can have multipul seperate vms facing the internet . Has anyone tried any adsl cards for "desktop" systems?
Setup a basic modem in bridge mode with whatever ethernet-based routing/server setup you want behind it.
If having the modem in the same box as the rest of your stuff is an absolute must have requirement, there is this one card that can do it: http://traverse.kd85.com/
It's basically a single board ADSL modem that acts like a pci-e ethernet adapter, it offers zero advantages over using an external modem. In fact, it makes your setup more prone to catastrophic failure (spikes on the phone line go straight into your server PC, including lightning strikes), and the setup process is tedious.
Spikes along the phone line can kill your server and/or anything connected to it