SPACI score report for 3nx6 in ASTRAL 2.07:

PDB Entry: 3nx6
SPACI score: 0.4
AEROSPACI score: 0.4

Experiment type: XRAY
Resolution: 1.97
R-factor: 0.217
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 1.061
WCK2 WHAT_CHECK Ramachandran: -1.927
WCK3 WHAT_CHECK Chi angles: -5.349
WCK4 WHAT_CHECK Backbone: 1.046

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).