To hit such high efficiencies, Google calls for a power supply design that outputs only 12V power. Existing desktop PSUs split power into multiple lines—12V, 5V, and 3.3V—but Google's white paper says this design actually requires four different power supplies, making it harder to achieve higher efficiencies. The whitepaper says the multi-voltage system is a carry-over from the IBM PC days, and that chips today no longer need 5V and 3.3V lines because they use voltage regulators directly on the motherboard to achieve ever-changing and usually decreasing voltages.
The simpler 12V-only design would remove the unnecessary middle-men and facilitate the building of more efficient PSUs. Google is already using this design in its own server power supplies, and is currently working with Intel and other companies on an open industry standard to bring efficient 12V-only PSUs to PCs everywhere.