Nobody burns in MAC addresses. MAC is usually stored on eeprom. Either in BIOS or small i2c one on the NIC. Storing it in the nvram means you save $0.1 BOM, don

Nobody burns in MAC addresses. MAC is usually stored on eeprom. Either in BIOS or small i2c one on the NIC. Storing it in the nvram means you save $0.1 BOM, dont have to partition your bios chip and serialization becomes cheaper and faster. Its not like losing one is a problem, just bang a random number with Sun prefix and you will be statistically fine.