Please post server hardware configurations that worked (or didn't work) with Debian here. If it didn't work right out of the box with "standard" Debian CD/ISOs, please list what you did to make it work, such as compiling a new kernel with a specific driver included. Include make, model and specific configuration of server (eg. any addon cards).
It's hard to find out what to buy to run Debian on, since server configurations are less vanilla than regular desktop computers. I'm hoping we can help each other this way.
If possible, include what hardware had the problem (eg. the specific chipset model, the specific RAID card, or similar) and specifically what you needed to do to get it working at least partially/fully.
Current stock Debian 4.0 (Etch) runs the 2.6.18 Kernel.
Debian 3.1 (Sarge) runs the 2.4.27 or 2.6.8 Kernel.
see http://wiki.debian.org/ServerHardware/Sarge for sarge
Known supportive vendors
Please post to this page, making it a community effort to help each other out.