did you hook up EPS_12v_2? or leave it disconnected with the new psu?
I connected EPS_12v_2 with the new PSU. Apparently this isn't required but it might help if going to 4 modules.
I saw this on the Avalon wiki, it only mentions 1x unless they didn't update it for 4 modules
The PSU Spec
155mm recommend, MAX: 170mm
For 3 module units: 650W, 48A 12V, at least. recommend for a 20% margin.
For 4 module units: 750W, 60A 12V, at least. recommend for a 20% margin.
Plugs:
1X ATX 24PIN
1X EPS 12V (8PIN)
2X PCIE 12V (8PIN)