Asus mainboards use BIOS based on AMI micro-code. The first page looks the same on Asus boards of all types:
The second page called Ai Tweaker will determine everything. It contains almost all overclocking related settings and it didn’t disappoint us. Even a quick glance at the available functionality is enough to understand that none of the features have been cut off:
By setting Ai Overclock Tuner to Manual, we can adjust the FSB frequency in the interval from 200 to 800 MHz and PCI Express frequency in the interval from 100 to 180 MHz. FSB Strap to North Bridge parameter is set automatically depending on the FSB and memory bus frequencies and can be at 200, 266, 333 and 400 MHz. If you haven’t changed its setting, then DRAM Frequency parameter will show the entire list of available memory frequencies. It is very convenient that once the FSB frequency is changed, the DRAM Frequency parameter will be adjusted accordingly showing the actual memory frequency at the time.
Three informational lines right below the DRAM Timing Control parameter show the current memory timings settings. If you set DRAM Timing Control to Manual, you will be able to adjust all of them yourself:
DRAM Static Read Control, DRAM Read Training and MEM. OC Charger parameters are also very important. They may be set to Auto, Enabled or Disabled, and help improve the memory’s ability to work at higher frequencies. Ai Clock Twister parameter has direct influence on the memory overclocking potential and its performance. It may be set to one of the following:
Ai Transaction Booster parameter allows changing Performance Level - a very important setting that has serious effect on the memory subsystem performance.
The next group of settings deals with mainboard chipset fine tuning and the possible settings for CPU Margin Enhancement parameter speak for themselves: