I posted this test position on this forum a year and a half ago. As far as I can remember, only a development version of Zappa (with history pruning off I believe) found it on a 8-way opteron in 8min or so then. Are the newest beast able to find this on a quad quickly?
[d]r2q1rk1/1bpp1p2/pb5p/1p4N1/3Pn2B/1Q6/PP3PPP/RN2R1K1 w - - 0 16
Best move: Rxe4!
Test Position Negi-Spoelman 2007
Moderator: Ras