There's also just the sheer bandwidth factor. A GTX Titan has 288 GB/s of BW, a Haswell with DDR3 puts out about 35 GB/s. That's a factor of 8.22x more bandwidth, so there's your 8x speedup.
It's a highly memory-limited task so I suspect that's where any speedup would come from.
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There's also just the sheer bandwidth factor. A GTX Titan has 288 GB/s of BW, a Haswell with DDR3 puts out about 35 GB/s. That's a factor of 8.22x more bandwidth, so there's your 8x speedup.
It's a highly memory-limited task so I suspect that's where any speedup would come from.