Ever since the cryptocurrency market heated up again, the video card market has been terrible. Consumers who wanted to buy a GPU have been stuck choosing between paying a 1.5x – 2x cost premium over standard MSRP or simply going without. Investors have been jittery about the end of the boom; AMD and Nvidia stock both took a hit when even rumors of an ASIC from Bitmain that could be used to mine cryptocurrencies might be headed to market. Now that same ASIC is supposedly ready for prime time — but there’s a major caveat attached.

To dig into how an ASIC works in this context, we first need to note that the way this topic is framed is often rather messy. A GPU is an ASIC. It’s an application-specific integrated circuit for handling games and 3D applications, or at least it used to be. Over the last decade, GPUs have steadily become more programmable and flexible; Nvidia’s work on CUDA has led to GPUs being used for workloads and in areas that were once the exclusive domain of CPUs, including oil and gas research, computational fluid dynamics, self-driving vehicles, AI and machine learning, and other HPC applications.

A GPU is still an ASIC, but it’s a programmable, flexible ASIC. Equally important, it’s an ASIC that spends a significant amount of logic and power on features that aren’t needed in a device dedicated to hashing cryptocurrency. Historically, the appearance of dedicated mining ASICs has meant the end of GPU mining, simply because there’s no way for AMD or Nvidia to compete with the potential hash performance of a dedicated circuit. Bitmain’s ASIC could mean the end of cryptocurrency mining on GPUs — but there’s at least two reasons to doubt it.

First, we’ve got to strongly caution anyone considering taking the plunge on an ASIC miner for cryptocurrency, period. Four to five years ago, when the first Bitcoin ASIC and FPGA miners launched, people rushed to order them, only to wind up losing hundreds to thousands of dollars. In many cases, it took companies 6-12 months to deliver products they promised would ship in a matter of weeks — and that assumes the company in question didn’t collapse after committing financial fraud. That alone is good reason to be cautious.

Bitmain is promising that the Antminer E3 will mine ethereum at 180MH/s with a power consumption of 800W and an $800 price tag. Availability is expected in July.

It’s not clear how much of a gain this is over GPUs. Overclockers3D didn’t think it was all that much, and it doesn’t seem to be as large as the gains when BTC moved to ASICs, but I suspect it could still be a noticeable improvement. But all of that’s secondary to a larger issue: the Ethereum community might hard fork the currency before they accept Ethereum ASIC mining. Many cryptocurrency enthusiasts are wary of the massive centralized infrastructure that Bitcoin developed and its domination by a tiny group of the largest firms.

Ethereum is designed to prevent this kind of centralization by ASIC. Here’s how the Ethereum white paper describes it:

The current intent at Ethereum is to use a mining algorithm where miners are required to fetch random data from the state, compute some randomly selected transactions from the last N blocks in the blockchain, and return the hash of the result… Ethereum contracts can include any kind of computation, so an Ethereum ASIC would essentially be an ASIC for general computation – ie. a better CPU… One notably interesting feature of this algorithm is that it allows anyone to “poison the well”, by introducing a large number of contracts into the blockchain specifically designed to stymie certain ASICs. The economic incentives exist for ASIC manufacturers to use such a trick to attack each other. Thus, the solution that we are developing is ultimately an adaptive economic human solution rather than purely a technical one.

In a recent poll, when asked if Ethereum users would support a hard fork to block ASIC mining, 57 percent of the user base said they would. That doesn’t mean such a fork will happen, but it might not be a good idea to plunk down $800 for one of those Bitmain units. By the time July rolls around, these units may not be worth much.