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CPU NB performance tuning through the BIOS menu: 1) Set the CPU NB clock speed up to the next available va lue (example: if 1800MHz / x9 is the default and
NB clock testing via AMD OverDrive utility w as OK at 2000MHz then set CPU NB BIOS item to
2000MHz / x10 now)
2) Set CPU NB Voltage to a kno wn stable value (based on the NB clock testin g done thru AMD OverDrive
utility)
3) Keep HT Link multiplier at default value or lower it by one step (example: 2400MH z or x12 in the case
of the AMD FX-8150 CPU)
4) Set CPU Core Multiplier(s) / Voltage to a known stable setting before proceeding with CPU NB
performance tuning (to ensure that CPU core doesn’t cause stability issues / crashes)
5) Set Memory clock and timings to kno wn stable settings (example: DDR3-1333 CL9-9-9) note that
Memory interface will also be overclocked when HT ref. clock is adjusted. Memory must be able to run
10% above default clock during the CPU NB tests. Set Memory to DDR3-1333 and boost Memory
voltage to 1.600V to ensure stability
6) Reboot the system with the new CPU NB Multiplier / Voltage value and c ontinue HT ref. clock testing
thru AMD OverDrive™ utility (as instructed in the previous section)
Figure 8: CPU NB settings to adjust from the BIOS menu
The alternative approach is to adjust all the items directly from the BIOS menu and utilize a bootable stand-
alone stability tester such as Memtest86 or Memtest86+ (may be installed on a bootable USB key).
Please refer to “AMD “Scorpius” Platform Technology Performance T uning Targets” for the expected / o ptimal
Multiplier and VID values.
PLEASE NOTE THAT THE AMD PRODUCT WARRANTY DOES NOT COVER DAMAGES C AUSED BY
RUNNING COMPONENTS OUTSIDE OF SPECIFICATION INCLUDING DAMAGES CAUSED BY
OVERCLOCKING (EVEN WHEN OVERCLOCKING IS ENABLED WITH THE AMD OVERDRIV E UTILITY).