You are correct, they do not mine BTC..but you can mine BCC its a scrypt based coin. You can mine it with a GPU, but I dont recommend that, since that is not a profitable way of mining, use an ASIC machine, the results will be better.. I posted up a blog about how I went about it, and how I came to invest into it. ..Hope you find it helpful..cheers!

https://steemit.com/bitconnect/@ian4221/yep-i-did-it-taking-the-plunge-into-bitconnect