Error Messages. Part IV

In this article you can find the main error messages for AMIBIOS and AwardBIOS.


Mem Optimal Error A memory size in A channel does not comply with a memory size in B channel, as a result, the performance of the memory may be decreased.
Memory Parity Error A memory parity error. An error address may be additionally given.
Memory test fail;

Memory verify error at


The errors were found during testing of operating memory. The information on their types and address may be additionally given.
Missing Operating System; Missing OS;


No Operating System Found;

Not Boot Device Available

Operating system is missed (damaged) or boot device is unavailable. Check if the boot sequence in BIOS, connection and parameters of boot device (it is usually a hard disk) are correct.
NVRAM Checksum Error;

NVRAM Cleared;

NVRAM Data Invalid

NVRAM checksum error, the data are cleared.
NVRAM Cleared by Jumper NVRAM data were cleared with the help of a jumper on a motherboard.
OC fail, please enter setup to change OC Fail settings An overclocking of the system was failed. Check the frequency values of the SBus and multiplying processor ratio.
Operating System Not Found Operating System was not found on a boot device.
Override enabled – Defaults Loaded The system could not boot using the current parameters of CMOS configuration, so all values were downloaded by default.
Parity Error;

RAM parity error – checking for segment

Parity error. A source or address of an error may be given additionally.
PCI I/O Port Conflict;

PCI IRQ Conflict;

PCI Memory Conflict

Two PCI-devices try to use the same recourse: I/O port, IRQ or Memory. Check the functionality of the devices and parameters of resource allocation.
Press a key to reboot The system will reboot after pressing any key. This phrase usually occurs after a message about some critical error.