Second-hand CPU vs brand new GPU

[mackerel]

Originally Posted by Mark Rose

Rumours are Vega 20 will have 1/2 DP in 2018.

I only just saw the leaked slides claiming that. Not much to go on. Target 2H 2018, 7nm process, 1/2 DP compared to Vega 10's 1/16, same number of CU. Assuming similar clock rates, that could put Vega 20 around 6 DP TFLOPS. That could do some damage! But 1.5 to 2 years wait to find out...

Vega 10 in 1H 2017 is claimed to be about 750 DP GFLOPS, so somewhat reversing the recent trend.

I would speculate, given the trend to offer increased FLOPS at reduced precision, maybe they will have a way to do the same the other way with good efficiency? 1/2 rate is pretty much the best case. Or maybe they don't have a good way and will rely on 7nm process to give them the transistor budget to squeeze it all in.

[fivemack]

ECM results: 32 threads on dual-E5-2650 box do 1280 stage-1 ECM curves on a C194 in about 128000 seconds and 26.8 megajoules; one GTX1080 does 1280 stage-1 ECM curves on the same C194 in about 60000 seconds and 7.6 megajoules.

(stage-2 curves take about 706 thread-seconds on the E5-2650, so one box can keep up with two GPUs)