Start with a almsot-new E520n running feisty fawn, procured from craigslist. It only took a few minutes to decide this was a more worthwhile system than the old homebuilt brute. (Well that, and the fact that the old box had already died five or six times.)
Add in a spare 160GB SATA drive, to migrate off various files from the old system. (I bought some Dell style SATA cables on eBay.)
Fast forward a week, and I’m getting tired of only having one analog VGA connector to feed one of two DVI capable 20” displays.
I looked up the two lowest priced Nvidia based dual DVI cards. The 7600GT and 8600GT were within a dollar of each other, and both were in stock. Thinking about the Directx 10 type advantages in the “8” family, I bought the 8600GT.
Starting with a fresh re-install of Ubuntu 7.04 on a spare drive, and Envy and the Nvidia drivers, I was able to get the system working properly on dual monitors.