bios e memory - by ME and NO TIN - excuse me!

Hi,
I have a Intel Pentium4 CPU 2.40GHz, Motherboard Asus P4S8X (ACPI
bios.revision 1005 beta 013 date10/23/2003) and Corsair CMX512-2700C2PT ram
module.
I wish set [Performance setting: Enable] but my system become instable.
I want to use this parameter "Enable" because the memory when it is writing
is more fast
Tell me how i can set it?

This is my setting bios :
Memory Frequency (MHz) : 166
DDR Voltage Adjustament : AUTO
SDRAM Cas Latency : 2T
SDRAM Ras to Cas Delay : 3T
SDRAM Ras Precharge Time : 3T
SDRAM RAS Active Time : 7T
Chipset Clock Mode : Performance
SDRAM Command Lead-off Time : 1T
SDRAM One Page Control : Enable
Performance setting: Disable

I use for the Benchmark AIDA32 v3.93 :
- read 2161 MB/s
- write 361 MB/s If "Performance setting" is Enable, the memory write become
740/750 !!!

Thanks very much !!!!!!