Parameters of Chipset and Buses Overclocking. Part II

FSB Strap to North Bridge

This parameter is used in some motherboards for setting an operation mode of northern bridge of a chipset, depending on the FSB frequency.

Possible values:

  • Auto – the chipset parameters are set automatically (this value is recommended computer operation in its normal mode);
  • 200 MHz, 266 MHz, 333 MHz, 400MHz – the FSB frequency for which the chipset operation mode is set. Higher values increase the maximum possible FSB frequency while overclocking but decrease the chipset productivity. As a rule, an optimal value of this parameter while overclocking has to be chosen experimentally.

Supply Voltage Adjustment of Chipset

In addition to supply voltage of processor and memory, some motherboards also allow regulating the voltage of chipset components and levels of signals. The title of appropriate parameters may vary depending on the motherboard manufacturer. Here are some examples:

□ Chipset Core PCIE Voltage;

□ MCH & PCIE 1.5V Voltage;

□ PCH Core (PCH 1,05/1,8);

□ IOH Core;

□ NF4 Chipset Voltage;

□ PCIE Voltage;

□ FSB OverVoltage Control;

□ NВ Voltage (NBVcore);

□ SB I/O Power;

□ SB Core Power.

Practice shows that in most cases change of specified voltages does not give any effect, so leave the value “Auto (Normal)” for these voltages.

Spread Spectrum

Unintended magnetic radiation occurs during operation of modern computer components on high frequencies. This can be the source of interferences for various electronic devices. To decrease a little the amount of radiation impulses, you may use clock spectral modulation that makes radiation more uniform.

Possible values:

  • Enabled – a clock modulation mode is on; this decrease a little a level of electromagnetic interferences from a system block;
  • 25%, 0.5% – modulation level in percent (it is set in some versions of BIOS);
  • Disabled – the Spread Spectrum mode is off.


Always switch off Spread Spectrum for stable system operation during overclocking.

Some motherboards models have several independent parameters which manage the Spread Manage mode for separate components of the system, for example CPU Spread Spectrum, SATA Spread Spectrum, PCIE Spread Spectrum and others.