recommendations for multi-user X11

[Ross Gohlke]

I'm setting up a colocated server (not yet procured) as a remote X11 
environment for 10 business users with broadband Internet access.
It will be their primary work computer, offering a full suite of 
applications.  
Graphics-wise, they are not playing video games or watching movies but 
will want to view the occasional YouTube clip.

What are the graphics requirements of X11 in a low-video, multi-user 
environment?
What do you recommend for hardware?

This is for a 1U enclosure.
I would like to do it as cheaply as possible.
- Slot type for card upgrade - PCI-X is the most ubiquitous for 1U; 
would it work?
- Minimum on-board RAM
- Chipset - GeForce?
- Video card
- Motherboard - I'm looking at Tyan GX28 (2881)
http://www.tyan.com/archive/products/html/gx28b2881_spec.html


Thanks.

Ross Gohlke