Each time the BIOS loads the operating system on a blade, a power-on self-test (POST) is performed. This low-level, built-in diagnostics program verifies that the blade's hardware is present and operating correctly before the boot process actually begins. The POST contains instructions used to check the memory, system bus, and the master boot record. The POST screen displays copyrighted messages; BIOS version (and build information); number, type, and speed of the CPU(s) installed; chipset revision; and Option ROM.
The maximum memory size for the Sun Blade 8400 and 8420 is 64 Gbytes. The maximum memory size for the Sun Blade 8440 is 128 Gbytes. The BIOS POST determines the amount of memory actually installed in a blade, configures the memory controller, and tests memory during initialization.