Anandtech has some compute benchmarks for the 980: http://www.anandtech.com/show/8526/nvidia-geforce-gtx-980-re...

unfortunately I don't know which of these are representative of typical deep learning workloads, i.e. lots of GEMM calls, basically. A discussion about this is ongoing on the G+ Deep Learning community as well: https://plus.google.com/+SanderDieleman/posts/7ua9oCdRFV7

This thread on the NVIDIA forums is also interesting, someone mentions they achieved > 6 TFlops for SGEMM on an overclocked GTX 980: https://devtalk.nvidia.com/default/topic/776043/cuda-program...

If the article is correct (saying that the memory bandwidth is very important) then a 780Ti is still interesting (336GB/s[1] vs 224GB/s[2]). They increased the memory clock but they decreased the memory interface width from 384 to 256-bit, for some reason.

[1] http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-780...

[2] http://www.geforce.com/hardware/desktop-gpus/geforce-gtx-980...

nVidia released the first level cutdown (GM204) as the "80" part, while it really should be the 960 at most - the full/big Maxwell core hasn't been released yet.

Chances are the first fabbed version simply didn't work and they're waiting for the GM210.

Hmm. I am thinking about to get additional two GPUs for my configuration. 980 indeed sounds interesting, but the memory is too small. Any rumors about when NVIDIA plan to release a 6G+ card at similar price point as Titan?

No rumors, but it would make sense to come out about a year after they released the Titan black, which itself was about a year after they released the original Titan.