Past a certain point the cards won't support CUDA or Firestream, so no, you can't have a miner that will simply run on anything. Very old cards probably aren't worth running the software on anyway.

Moore's law states that complexity in a computer system doubles every 18 months. It's held true for more than 30 years (and actually seems to be accelerating). So, if your card is 18 months old, it's half as fast as a modern card. Three years old and it's 1/4 as fast. Four and a half years and it's 1/8. Six years and it's 1/16.

It's unfortunate that those with very restricted capital and old hardware can't do much on bitcoin, but there's nothing that can be done about it. You have to either get better hardware, suffer with what you've got or don't mine at all. Sorry.

I'm a software engineer working for a fortune 500 company looking to produce an open source CAL miner. I've got extensive experience in the software world, including development of software to analyze military communications traffic (I work for the Department of Defense), so expect great things!

I'll be seeing if I can get on Kickstarter so I can fund the purchase of some hardware to develop with, since I've only got a feeble little 4870 to work with now. Once the miner is released, the source will be published under the GPL and the hardware I purchase with Kickstarter funds will be given to my top beneficiaries (minus one card to continue development with).

Looking forward to being a part of the community and kicking CAL miners into high gear!

Hey there, OpenMining here. I'm a software engineer planning on building some GPL licensed open source mining software.