A Radeon HD 6990 for hash cracking. Good or bad idea?

[Flomac]

That's the problem with the 295X under stress (comparable to hashcat):
https://www.youtube.com/watch?v=YCIZJW-aPaE

There is a serious design problem with the voltage regulators which reach up to 107°C. They are neither properly designed or cooled for these loads. Look in the middle of the card:




And how it's done right (1-slot ASUS ARESIII):




Buying Nvidia for Hashcat is clever, GTX970 has a good price/performance value, the GTX980 very well and the GTX960 is great value for half the 980-performance. It outperformes the 750Ti clearly and is merely more expensive. All these cards run much more efficient than comparable AMDs, so less power and less heat.

The 390X might be a game changer again, although I read it'll come with a stock water cooler.