4.4.1 Summary of Warning Messages

(Jumperless Operation only)

The system may crash or hang up due to conflicts between settings and CPU compatibility: checksum errors, improper frequency settings, change of CPU and improper CPU speed settings. The system starts up in safe mode running at a bus speed of 100MHz and enters the BIOS Setup. Each time a system hangup occurs, BIOS interrupts the bootup process with a specific warning message. These messages always appear on the right side of the BIOS screen in red print:

1.Cause for Hangup: Checksum Error Warning

“The CMOS checksum is incorrect. Please reload the cmos default value.” To solve this problem, clear the CMOS RTC memory (see pages 22 and 59) and then reenter the default values in the BIOS Exit menu and restart the system.

2.Cause for Hangup: Improper System Frequency

“Last time you failed to change the frequency of the system. It may place the system into an unstable state. Now the system is in safe mode at the slowest CPU speed. Please set the system frequency again.” To solve this problem, a slower frequency is more likely to obtain stable start-ups.

CPU Upgrade/Reinstallation

To ensure that the system can enter BIOS Setup after replacing the processor, the system starts up running at a bus speed of 100MHz and a fail-safe CPU internal frequency. Then it automatically enters the Advanced menu with a popup display of all the possible CPU internal frequencies for the particular CPU presently installed:

3.Cause for Hangup: Improper CPU Speed 1

“During the last bootup, your system hung for an improper CPU Speed setting. Your system is now working in safe mode. To optimize the system performance and stability, make sure the CPU speed conforms to the specifications of your CPU.”

4.Cause for Hangup: Improper CPU Speed 2

“Since you are using a new CPU or have reinstalled your CPU, the system boots up at the slowest CPU bus frequency to make sure the system can enter setup menu. Now, you can adjust the CPU speed as you wish. If the speed is adjusted too high, the system may hang. Please turn off the system and then restart to set the CPU speed.”

ASUS A7N266-VM motherboard user guide

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