Did this bench out of curiosity to see how a 4c4t ryzen cpu would compare against a Skylake and Core2 4c4t CPU both at 4Ghz, this wasnt a serious bench by any means. Also note that the cpus config was at 2+2 and also the mem was at 2933MT/S and had the full 16MB of L3 cache so its not quite an apples to apples comparison...but probably good enough.
I must say im quite surprised by the result tho as the Core2s i looked at got 12mins 30 and the Skylake got 10 mins 30.