time povray -D +a solve_centenario.pov +k5.2

on different boxes:

---------------------------------------------------------------------
abacus
---------------------------------------------------------------------

---------------------------------------------------------------------
babbage
---------------------------------------------------------------------

Render Time:
  Photon Time:      No photons
  Radiosity Time:   No radiosity
  Trace Time:       0 hours  1 minutes 45 seconds (105.761 seconds)
              using 20 thread(s) with 1475.072 CPU-seconds total

real    1m47.841s
user    24m36.389s
sys     0m0.220s

---------------------------------------------------------------------
euclide
---------------------------------------------------------------------

Render Time:
  Photon Time:      No photons
  Radiosity Time:   No radiosity
  Trace Time:       0 hours  6 minutes 31 seconds (391.498 seconds)
              using 4 thread(s) with 1530.900 CPU-seconds total

real    6m33.439s
user    25m32.075s
sys     0m0.186s

---------------------------------------------------------------------
krylov:
---------------------------------------------------------------------

Render Time:
  Photon Time:      No photons
  Radiosity Time:   No radiosity
  Trace Time:       0 hours  2 minutes 52 seconds (172.450 seconds)
              using 12 thread(s) with 1786.029 CPU-seconds total

real    2m54.041s
user    29m46.911s
sys     0m0.146s

---------------------------------------------------------------------
wilkins
---------------------------------------------------------------------

Render Time:
  Photon Time:      No photons
  Radiosity Time:   No radiosity
  Trace Time:       0 hours 11 minutes 17 seconds (677.527 seconds)
              using 4 thread(s) with 2615.585 CPU-seconds total

real    11m20.119s
user    43m36.243s
sys     0m1.878s