01-11-2015, 09:16 PM
(01-05-2015, 03:59 AM)epixoip Wrote: Just because a card is more expensive does not mean it will be better for hash cracking. Graphics cards are designed for graphics, and just because a card is better than another at pushing pixels, doesn't mean it will be better for compute. With Nvidia GPUs, you have to ignore everything prior to the Maxwell microarchitecture, as they are not good for hash cracking. The GTX 980 is the first Nvidia card in 6+ years that is actually good at hash cracking, and in fact slaughters AMD in anything that involves memory.
Bus width matters, but it's not what you should be primarily looking at. What matters most is the instruction set and the number of instructions that can be executed per second, neither of which you will find in the marketing docs. Power consumption and cooling capabilities are important as well. We always buy reference design cards when possible as OEM-design cards are designed for gaming workloads and cannot keep up with compute workloads, especially in multi-GPU setups.
The best cards for hash cracking are, in order of preference:
1. Nvidia GTX 980 reference design
The 7990 and 6990 are omitted from this list because they are a nightmare to deal with.
So how does the GTX 980 compare to a 7990 - ive got one thats watercooled - but would maybe look at changing it to the 980 if its a lot better?