Most people here are engineers and can see through the buzz words all these crypto tokens are throwing around to lure in naive investors. So it's assumed that it is a bubble as majority of tokens are worthless from technical perspective.

In the short term I think we may see Bitfinex/Tether blow up pretty soon. Just this last week they printed around $500M in fake money to keep bitcoin prices from falling.

It doesn't have to crash. It just has to be uneconomic to mine on GPU's. For example by becoming too hard, or by switching to proof-of-stake. The question is rather whether there is another coin that will take over the workload of the rigs (I know too little about cryptocurrencies to know whether another coin will have the same properties as ether, i.e. be economic to mine on GPUs).

It's basically as if there were 300 new social media networks all popping up within 1 year, and 99% of them were clones of an open-source social media github, with a few minor alterations and a ton of marketing fluff, with perhaps 2-3 social media networks (Facebook, Instagram, Reddit) commanding 90% of the market.

There's just no utility behind all these coins. Hell, there aren't even any significant amount of bitcoin users, let alone Ethereum or Ripple, or any of the ridiculous coins. They're all presenting themselves as interesting for their utility, but are valued as an extremely short-term store of value play. It just can't last.

Lastly, note that there's only 3 cryptos that have a market cap of at least 10% of that of Bitcoin, and one is Bitcoin Cash so it doesn't count. The other are Ripple and Ethereum. Ripple has proof of stake (i.e., no mining is necessary) and Ethereum is expected to go proof of stake in the next hard fork, likely this year.

Just to put that into perspective. Nvidia's revenues are about $7b a year, AMD about 4 billion, let's say together 12b. They command pretty much 100% of the discrete GPU market, with Intel being the major integrated market player that is irrelevant in this context. Then look at https://digiconomist.net/ethereum-energy-consumption for an idea about mining revenues. It's about $14b a year, and electricity costs estimate the after-electricity profits at about $12b a year. Now you'd expect that a miner who can make $12 by turning on a device (with its electricity already paid for), is willing to pay anywhere between $0 and $12, and that with enough competition, they'll spend close to $12.

That gives you a rough idea about how significant Ethereum is as a player, with Bitcoin running on Asics and Ripple already at Proof of Stake, and most other coins being quite insignificant (and also a combination of Proof of Stake or Asics based like Litecoin, anyway).

So in short: I think cryptos will crash and even if a lot of them remain, I argue a lot of this price pressure is due to the few big coins of which only ethereum has viable GPU mining and that'll end in 2018.

Depends how far they crash. If it's cheap enough, it might be a worthwhile trade-off.

I recently learned a really fascinating stuff about semiconductors: as they heat up, the doping atoms tend to move, by diffusion. Heat = more diffusion.

I've read that thermal cycles do more damage than constant running.

On the other hand, you can be sure these cards have made it well past the "infant mortality" part of the bathtub curve.

In fact, military and other high-reliability applications specify "burn-in" periods where components are operated at elevated temperatures for several hundred hours --- they are effectively "used":

http://reliabilityanalytics.com/reliability_engineering_libr...

If I can buy a 1080 for $100 when they flood ebay, I'm willing to take my chances.