User`s manual
Appendix B: BIOS POST Codes
B-3
POST Code Description
49h Initialize PCI bus and devices
4Ah Initialize all video adapters in system
4Bh QuietBoot start (optional)
4Ch Shadow video BIOS ROM
4Eh Display BIOS copyright notice
4Fh Initialize MultiBoot
50h Display CPU type and speed
51h Initialize EISA board (optional)
52h Test keyboard
54h Set key click if enabled
55h Enable USB devices
58h 2-2-3-1 Test for unexpected interrupts
59h Initialize POST display service
5Ah Display prompt “Press <ESC> to enter SETUP”
5Bh Disable CPU cache
5Ch Test RAM between 512 and 640 kB
60h Test extended memory
62h Test extended memory address lines
64h Jump to UserPatch1
66h Congure advanced cache registers
67h Initialize Multi Processor APIC
68h Enable external and CPU caches
69h Setup System Management Mode (SMM) area
6Ah Display external L2 cache size
6Bh Load custom defaults (optional)
6Ch Display shadow-area message
70h Display error messages
72h Check for conguration errors
76h Check for keyboard errors
7Ch Set up hardware interrupt vectors
7Dh Initialize Intelligent System Monitoring (optional)
7Eh Initialize coprocessor if present