ASUS uses a modified version of the American Megatrends AMIBIOS for their motherboards. The menu is split into Main, Ai Tweaker, Advanced, Power, Boot, Tools and Exit. The Main Menu is where you get the system time, date, storage information and Configuration. Here is where you set the HDDs or SSDs to RAID.
The Advanced Menu is where the CPU Configuration screen, the Chipset menu, the onboard devices menu, the USB Configuration menu and the PCIPnP menu is located. The CPU configuration menu is where you set the CPU Ratio setting and enable the CPU features like C1E and Virtualization technology. The chipset menu is where the North bridge and VT-d configuration is set.
The onboard devices menu is where the High Definition Audio is enabled or disabled as well as the Marvell LAN ports, Firewire, and Marvell 9123 controller. USB Configuration is where the USB 3.0 and 2.0 controllers are enabled disabled. Here is also where the Legacy USB support is set. PCIPnP is where the Plug and Play OS is enabled.
Most of the tweaking is done in the Ai Tweaker menu. Here you can enable the Ai Overclock Tuner which goes to Manual, Auto, DOCP (Overclocks DRAM frequency by adjusting BCLK frequency), and XMP (for memory modules supporting eXtreme Memory Profiles). The DRAM OC Profile will change your memory settings based upon the memory installed. The CPU Ratio setting allows you to change the CPU Ratio downward on locked processors and upward or downward on unlocked ones. I was able to overclock the Core i7 920 to 3.6GHz on the P6X58D Premium board using TurboV. Here’s a chart of the various settings available in the BIOS:
|
Setting | Range |
| BCLK | 100-500 |
| PCIE Frequency | 100-200 |
| DRAM Frequency | Varies with BCLK |
| UCLK Frequency | Varies with DRAM Frequency |
| QPI Link Data Rate | Auto 4726MT/s, 5778 MT/s, 6304 MT/s |
| DRAM Timing control | Varies on DIMMs installed |
| DRAM CAS Latency | 3 DRAM Clock, 4 DRAM Clock-10 DRAM Clock, 11 DRAM Clock |
| DRAM RAS to CAS Delay | 3 DRAM Clock, 4 DRAM Clock-9 DRAM Clock, 10 DRAM Clock |
| DRAM RAS PRE Time | 3 DRAM Clock, 4 DRAM Clock-9 DRAM Clock, 10 DRAM Clock |
| DRAM RAS ACT Time | 3 DRAM Clock, 4 DRAM Clock-30 DRAM Clock, 31 DRAM Clock |
| DRAM RAS to RAS Delay | 1 DRAM Clock-7 DRAM Clock |
| DRAM Ref Cycle Time | 36 DRAM Clock, 48 DRAM Clock, 60 DRAM Clock, 72 DRAM Clock, 82 DRAM Clock, 88 DRAM Clock, 90 DRAM Clock, 100 DRAM Clock, 110 DRAM Clock |
| DRAM Write Recovery Time | 1 DRAM Clock-15 DRAM Clock |
| DRAM READ TO PRE time | 3 DRAM Clock-15 DRAM Clock |
| DRAM FOUR ACT WIN Time | 1 DRAM Clock-63 DRAM Clock |
| DRAM Back to back CAS Delay | 4 DRAM Clock-32 DRAM Clock |
| DRAM Timing mode | 1N, 2N, 3N |
| DRAM Round Trip Latency on CHA | Advance 15 Clock- Advance 1 Clock, Delay 1 Clock-Delay 15 Clock |
| DRAM Round Trip latency on CHB | Advance 15 Clock- Advance 1 Clock, Delay 1 Clock-Delay 15 Clock |
| DRAM Round Trip latency on CHC | Advance 15 Clock- Advance 1 Clock, Delay 1 Clock-Delay 15 Clock |
| DRAM WRITE to READ OD Delay | 1 DRAM Clock-8 DRAM Clock |
| DRAM Write to READ DR Delay | 1 DRAM Clock-8 DRAM Clock |
| DRAM Write to READ SR Delay | 1 DRAM Clock-22 DRAM Clock |
| DRAM Read to Write delay (OD) | 2 DRAM Clock-14 DRAM Clock |
| DRAM Read to Write delay (DR) | 2 DRAM Clock-14 DRAM Clock |
| DRAM Read to Write delay (SR) | 2 DRAM Clock-14 DRAM Clock |
| CPU Voltage | 0.850000V-2.10000V in 0.00625V interval |
| CPU PLL Voltage | 1.8V-2.5V with 0.02V interval |
| QPI/DRAM Core Voltage | 1.20000V-1.90000V with a 0.00625V interval |
| IOH Voltage | 1.10V-1.70V with a 0.02V interval |
| IOH PCIE Voltage | 1.50V-2.76V with a 0.02V interval |
| ICH Voltage | 1.10V-1.4V with a 0.10V interval |
| ICH PCIE Voltage | 1.50V-1.80V with a 0.10V interval |
| DRAM Bus Voltage | 1.50V-2.46V with a 0.02V interval |
| DRAM DATA REF voltage on CHA/B/C | 0.395x-0.630x with a 0.005x interval |
| DRAM CTRL REF Voltage on CHA/B/C | 0.395x-0.630x with a 0.005x interval |
| CPU Differential Amplitude | 700mV, 800mV, 900mV, 1000mV |
| CPU Clock Skew | Auto, Normal, Delay 100ps, 200ps-Delay 1400ps, Delay 1500ps |
| IOH Clock Skew | Auto, Normal, Delay 100ps, 200ps-Delay 1400ps, Delay 1500ps |
