Thanks!
Blind as usual... anyways, Everest is showing the following for the PCIE 2.0 bus:
#1 x1 Marvell SATA 6Gb/s controller
#2 x1 NEC SUB 3.0 controller
#3 x8 GTX480
#7 x16 GTX480

Seems like GTX480 in the first slot (closest to CPU) is 'stuck' in x8??
Bad card or bad m/b?

Will switch the 480s later this week to see if things changes.