https://www.altera.com/content/dam/altera-www/global/en_US/pdfs/products/software/opencl/ieee-cp-information-filtering.pdf https://www.altera.com/content/dam/al

https://www.altera.com/content/dam/altera-www/global/en_US/pdfs/products/software/opencl/ieee-cp-information-filtering.pdf https://www.altera.com/content/dam/altera-www/global/en_US/p... "We show that our implementation achieves 5.5x and 5.25x better performance per watt ratios than GPU and CPU implementations, respectively." This is from Altera and they probably skewed to FPGA side. But still, FPGA can be very competitive if you consider power budget. Xeon Phi costs $3900: http://www.amazon.com/Intel-Xeon-Phi-7120P-Coprocessor/dp/B00FKG9R2Q http://www.amazon.com/Intel-Xeon-Phi-7120P-Coprocessor/dp/B0... It consumes up to 300W. The average kWh in USA is $0.12: http://www.npr.org/sections/money/2011/10/27/141766341/the-price-of-electricity-in-your-state http://www.npr.org/sections/money/2011/10/27/141766341/the-p... So Xeon Phi consumes up to $36 of electricity per hour, $864 per day and electricity start to dominate as quick as in 5 days. Typical FPGA consume about 10 times as less power as Xeon Phi.