Via our chief engineer in at a prominent audio post house in Chicago:
Yes, Sager is very helpful, and yes paying $95 instead of $350 to Avid is nice, but.....
Anyone ordering the part from Sager should be aware that the part that Avid uses in the board is part number is SNP-Z10B-D . notice the -D
What is the difference? On the Avid spec part there are insulators on both regulators on the power supply, isolating them from the metal where you attach the heat sync. Without that, there is a voltage on that metal. If you attach the Avid heat sync, you will short the supply to ground and it will never turn on. All you will hear is a clicking every half second.
The solution is either to;
a. order the SNP-Z10B-D .
b. DON'T use the Avid heat sync, and just use the small heat sync provided with the Sager power supply. (which is much easier, but might "void the warranty")