In this situation, all CRTCs will do an activation of HBORDER.
If R6=0 and VCC=0, we expect VBORDER to activate as VCC=R6 and we also expect VBORDER to deactivate as HCCVCC=0.
In this situation, all CRTCs will do an activation of VBORDER. But on CRTCs 0/2, the first raster line will show an alternation of bytes of VBORDER and displayable characters.