The types of computations needed for bitcoin to verify data are similar to the types of computations needed for complex graphics. So you need a Radeon, Nvidia or Intel GPU for that. Then there's an FGPA which is more efficient. ASIC miners check hashes, better than a CPU, or that a GPU can't do. Someone made an analogy that a CPU was a decision maker that distributed tasks, and the GPUs were good at heavy duty and plentiful work that didn't require decision making. Same for ASIC miners. At the beginning a CPU could be used, but to mine now, there will be quick competition from GPU's, ASIC's and FGPA's making the difficulty increase quickly that a CPU won't compete with.
Offtopic: I see potential use in ASICs useful for something other than cryptocurrency, for comparing content files.
I think Bitcoin will survive as a token, or artifact. It has faults, but will be gone when a better currency comes along. Faults of it include limited set stock, that early comers have a disproportionate advantage in its value, that distribution is still otherwise disproportionate based on who has more hardware, that verifying payments takes too long, high fees for transactions, the lost coins by hacks, and that it's commonly used as an artificial stock.
The head of a major banker criticized it (I think it was Chase), discouraged employees from using it, and IIRC said he would reprimand high level employees from using it. Then what do you know? He drove the value down with that statement, then hypocritically went in and bought Bitcoin to cash in on it. But apart from this, many statements against Bitcoin are based in reason, and are valid. It can be pointed out what an executive (CEO iirc) banker did to manipulate for greed and use existing wealth to disproportionally gain more. Warren Buffet has a reasonable and thoughtful argument about gold, that money, time and energy is spent to dig it up, then money, time and energy is spent to bury and guard it, in what can be referred to as intrinsic value. I don't remember if Buffet criticized cryptocurrency, but at least he usually believes what he says.
A cryptocurrency will survive, but as far as I know, one without inherent problems hasn't been created yet. Or maybe there will be difficulty in that, as an organization will control it from the start, unless there's a "fair" consortum, or that a motivation will be profit in a newly created stock.
The problem of wealth distribution in cryptocurrency is similar to that in hard or gold currency.
There aren't many practical uses for it, but you can buy legitimate websites with Bitcoin.