Is cloud computing going to be more cost-effective than a CPU?
I would expect the difficulty to quickly rise until Amazon EC2 is not profitable or only just barely so. After all, if it's profitable, why not immediately spin up more machines? Thus, EC2 likely sets the maximum cost/hash that will be profitable.
No, it is most expensive way if you're planning to mine in mid or long term.
Also keep in mind that actual memory bandwidth of virtual servers at these cloud providers is only few GB/s than frequently quoted 17GB/s of the mainstream DDR3 (can't remember source, I read this long ago). This means the performance against Equihash would be constrained furthermore.
What's a reasonable monthly rate for dedicated hardware?
Does anyone know the precise number for memory bandwith of amazon virtual servers ?
16 GB RAM dedicated (m4.xlarge) with AWS EC2 will cost $172 per month which is only a little less than a good deal on a used PC upgraded to 16 GB. And you can't upgrade to a GPU later on.
Also what's worth mentioning on Amazon instances is it allocates "# of vCPUS" to your instance size, but you have no way if knowing how many physical processors that is.
For example I order 4 vCPUs am I getting half of an 8 core processor? One 4 core processor? 1/3 of a 12 core processor? And what else is the rest of that processor doing? Is it idle or running at full tilt? What else is eating up my memory bandwidth? Is it DDR 2,3,4?
Amazon sounds good on paper but as others have mentioned, will likely not be a good long term solution.