CPU mining is not an obstacle but is not profitable at all.
BIS is a GPU coin, with specific algo to heavily penalize FPGAs and asics from common algorithms.
There are discussions about potential use of mining channels to have both GPU and CPU mining going on, but nothing practical as for now.
I personally believe that GPU is still the better path to hash power decentralization.
i highly doubt that only GPUs are mining this, if an algo can be reasonably mined by shitty old GPUs then FPGAs can do it profitably. maybe a 8gb minimum ram requirement for GPU's can be a good start, ETH crossed the 3gb minimum, BIS is currently at what?
BTW that "unnamed exchange" has an interface that looks like cryptopia LOL
Before our heavy3 algo, we had an FPGA mining op taking most of the rewards for a while.
The heavy3 algo was tailored to address that, and so far I have no hint that bis is mined by FPGA.
It's not only a question of total ram, but also of random reads and ram bandwidth.
GPU has better ram bandwidth than what fpga can do. And mining bis would require high end fpgas anyway, with ram. Becomes more common, but still.
With heavy3, simulations show that high end fpga can mine bis, but with no real leverage over GPUs, because of ram bandwidth..
If you have some insight info, or hints that bis is mined by fpga, please tell me more. If we have doubts, that will be addressed.
Btw, we are not against fpgas by principle. We are against hash power centralization, and one mining op, or one small class of miner taking all.