IEI Integration IMBA-9454 v4.02 - Manual (Page 158)

IMBA-9454G Motherboard
Page 140
BIOS SETUP UTILITY
Main Advanced PCIPnP Boot Security Chipset Exit
Southbridge Configuration

Spread Spectrum Mode
[Disabled]
Audio Controller [AC’97 Audio]
Enable/Disable Spread
Spectrum modulation.
 Select
Screen
  Select
Item
+ - Change Option
F1 General
Help
F10 Save and Exit
ESC Exit
v02.61 ©Copyright 1985-2006, American Megatrends, Inc.
BIOS Menu 23: Southbridge Chipset Configuration
 Spread Spectrum Mode [Disabled]
Use the Spread Spectrum option to reduce the EMI. Excess EMI is generated when the
system clock generator pulses have extreme values. Spreading the pulse spectrum
modulates changes in the extreme values from spikes to flat curves, thus reducing the
EMI. This benefit may in some cases be outweighed by problems with timing-critical
devices, such as a clock-sensitive SCSI device.

Disabled D EFAULT EMI not reduced

Enabled EMI reduced
 Audio Controller [AC’97 Audio]
Use the Audio Controller option to enable or disable the AC’97 CODEC.

AC’97 Audio D EFAULT The onboard AC’97 is disabled

All Disabled The onboard AC’97 automatically detected and
enabled