Ought to be just fine. You're nowhere close to the limits on the -12 and 5V rails, and only the +12V one is pushing it a bit. But as senor-bling mentioned, Dieter overspecced those power supplies. Even with an inrush, it should handle that like a champ. One thing I would suggest, though, is to try and balance that +12V load as evenly as possible across all three of your busboards. That should give you some leeway on power-up as well.