What are these cosmic parameters for bitrack?
I once stated exactly that -b is a parameter that should be equal to the number of "compute units" read with cuBitCrack -l, a -t parameter of 512 (or 256 if the newer card architecture doesn't let that big), and a floating parameter -p that it is necessary by trial and error to determine the most issued. Apart from the fact that you tire your GPU with the parameters you specify (not to mention the MKeys / s speed) - let me also remind you that VanitySearch has better performance when it comes to MKeys / s.
As for the right question of my predecessor - any not too old card will be good. At the current stage of development of all the above-mentioned applications - it is definitely worth paying attention to NVIDIA cards, because they are reliable on these cards, which cannot be mentioned about the OpenCL support that only BitCrack provides, and in addition with a different effect.
A colleague in front of me is somewhat misleading, because there was no question about how many cards he must have to find the key, but what card he must have in order to start participation, and these are two different issues. The same in terms of profitability. As you can see on the ttdsales.com/64bit/ pool, which is actively working to find the key to # 64 - apart from me, there is also a group of people who with little power, but still support the search, because each already proven range falls out of the pool of possibilities, and what a hence -> the number of possible ranges is constantly decreasing, but if in the end the correct key is found by these smaller participants (because the chance for this is greater with every moment when subsequent empty ranges fall off) - apart from the prize resulting from the score table - the participant will receive such a Pool owner bonus of $ 500 + from me another $ 500, so even entering the participation with little power -> you can get rich with a bit of luck by a minimum of $ 1000, and I will just mention that 16% of the range has already been checked.

As part of the development of this topic - I will gladly update the main post with the GPU performance charts in terms of speed achieved along with the best settings for both programs listed beside.
I remember that some time ago someone created something like that, taking into account the price of the GPU and the price-performance ratio, but I don't remember if it was in any of the previous topics on this challenge, such as VanitySearch, BitCrack or elsewhere, but if anyone remembers - I would be grateful for pointing to the link in order to be able to start developing the base version of this list. Creating it from scratch somehow I don't really want to go out :-)