SPACI score report for 3nn8 in ASTRAL 2.05:

PDB Entry: 3nn8
SPACI score: 0.21
AEROSPACI score: 0.21

Experiment type: XRAY
Resolution: 3.1
R-factor: 0.186
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 3
PCK3 PROCHECK H-bonds: 3
WCK1 WHAT_CHECK Packing: -0.183
WCK2 WHAT_CHECK Ramachandran: -3.117
WCK3 WHAT_CHECK Chi angles: -4.837
WCK4 WHAT_CHECK Backbone: -0.067

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).