Acer G901 manual 214

214		Appendix E: Codes and error messages
CP	Beeps	Reason
16	1-2-2-3	BIOS ROM checksum
18		8254 timer initialization
1A		8237 DMA controller initialization
1C		Reset Programmable Interrupt Controller
20	1-3-1-1	Test DRAM refresh
22	1-3-1-3	Test 8742 keyboard controller
24		Set ES segment register to 4 GB

281-3-3-1 Autosize DRAM, system BIOS stops execution here if the BIOS does not detect any usable memory DIMMs

2A		Clear 8 MB base RAM
2C	1-3-4-1	Base RAM failure, BIOS stops execution here if
		entire memory is bad
32		Test processor bus-clock frequency
34		Test CMOS
35		RAM initialize alternate chipset registers
36		Warm start shut down
37		Reinitialize the chipset
38		Shadow system BIOS ROM
39		Reinitialize the cache
3A		Autosize cache
3C		Configure advanced chipset registers
3D		Load alternate registers with CMOS values
40		Set initial processor speed new