No, it absolutely is not the best card to buy for oclHashcat. You are sorely mistaken. 2x 290X are cheaper, faster, and behave much more civilly. GTX 980 however is the all-around best card to buy.
The problem is not the with the program. The problem is with the card. The 295X is designed for gaming workloads, and absolutely not designed for compute workloads. As NBZ told you, if you know what you are doing, you can make the card behave a bit better through Powertune tuning & some hardware hacking. But it still won't be ideal.
The problem is not the with the program. The problem is with the card. The 295X is designed for gaming workloads, and absolutely not designed for compute workloads. As NBZ told you, if you know what you are doing, you can make the card behave a bit better through Powertune tuning & some hardware hacking. But it still won't be ideal.