There are a few critical elements to the computer I was seeking, it had to be fairly recent (2Ghz+/- processor speed), it needed a few Gig of memory (either present or at least capable of increase) and the storage needed to be fairly large (IDE 500Gig HD minimum).
The computer also needed to be capable of working with the Ebay 8 channel DVR card (sadly something I never know until it comes time to plug the damn thing in) and finally the computer needed to be inexpensive.
I may have acquired that computer yesterday. An HP Compaq Desktop, 2.8Ghz processor, 500Meg RAM (one slot used and one remaining open, SDRAM) and 40 Gig HD, along with onboard sound, NIC etc etc etc for $89.99 – A clean $100 after the gummint took their due).
The only problem with the PC appears to be the HP specific half height PCI slots, but thankfully the DVR card is half height, and it was a moments work with tin snips to get the card to fit with the case closed. Some quick exploring in Ubuntu and I confirmed that at least it was seeing 8 video devices (a good start), although all kinds of hardware detection errors kept threatening to rain on my parade.
In the end the card works fine. Up and running within a few hours. Higher resolution and frame rates chewed through 50% of the 40Gig drive in about 3 hours of experimentation (that was just one camera 640×480 at 25fps), upgrades are going to be imperative.
More experimentation with different distributions of Linux to see how much I can decrease the overhead without making the thing any more unfriendly than absolutely required.
Update: Satisfied that the DVR card works, I’m proceeding with upgrading both memory and storage, this requires some bargain shopping for DDR Ram and a 500Gig IDE drive so may take a bit of time. The good news is that experimentation with Linux doesn’t have to wait for the upgrades.