cMP² | CMP / 06BIOS

Chapter 6 - What is BIOS?

BIOS (basic input/output system) is software stored on a motherboard that configures the board, loads an operating system and manages the data flow between the central processor and devices such as the hard disk, video adapter, keyboard and mouse. A modern BIOS is flexible and careful configuration can significantly improve audio reproduction. Optimum settings for the recommended motherboard are described.

To change BIOS values, press the delete key repeatedly on power up to enter the first menu as shown. Be sure to press <Ctrl>+<F1> at the main menu to access advanced menu items. Navigate menus with the keyboard, pressing Enter to move down a menu tree and to edit parameters and Esc to move back up the menu tree. Once changes are made, go to Save & Exit Setup and hit Enter.

Test after each change outlined below so that the cause of any problem can be identified. Menus even in different versions of the same BIOS may differ but the pertinent parameters are usually easy to find. The text below goes through the procedure menu by menu. It is recommended that, before starting the setup, the user performs Load Optimized Defaults.

The operating system can be installed before or after making the BIOS changes but it is slightly simpler to do the BIOS setup first (except for disabling the floppy disk and IDE interfaces, used during setup).

Notes

If the BIOS fails to load the operating system due to an incorrect setting, default settings have to be restored. This is explained in Gigabyte’s manual. The feature is universal.
It is advisable to install the latest BIOS version, preferably after installing Win XP but before optimising it. Download it from Gigabyte’s web site and, using the supplied Q-Flash utility, copy the old BIOS, install the update and load the defaults as above. Refer to Gigabyte manual for more details on upgrading BIOS.
Version 1.45 or higher of CPU-Z can recognize the E7200 CPU. If BIOS changes have been made correctly, they should show the CPU, FSB and Vcc settings.
BIOS settings in red are high risk and requires a low temperature CPU setup.
Some settings may cause BIOS to lock and a CMOS reset is required. To reset BIOS from CMOS refer to Gigabyte manual for how 2 (be sure to disconnect power when doing this procedure).
GA-EG45M-UD2H mobo has a different and more complex BIOS setup. Follow the discussion here.

Standard CMOS Features

Disable Drive A (floppy disk drive)

Advanced BIOS Features

Disable:

1. HDD S.M.A.R.T. Capability

2. No-Execute Memory Protect

3. CPU Enhanced Halt (C1E)

4. CPU EIST Function (Allows for lower CPU VIDs)

5. CPU Thermal Monitor (TM2)

Set Init Display First to Onboard
Set Onboard VGA to Always Enable

Integrated Peripherals

Set On-Chip SATA Mode to Non-Combined
Disable Azalia codec, Onboard LAN Boot ROM, Serial & Parallel ports
Disable Onboard H/W LAN, SMART LAN (if not using networking functionality)
Disable USB 2.0 Controller (if NOT using USB soundcard)
Disable USB Keyboard and Mouse support (not used by Windows)
Disable Legacy USB storage detect (better to replace such devices)

Power Management Setup

Set ACPI Suspend Type to S1
Disable PME Event Wake-Up, Power On by Ring, Resume by Alarm, HPET Support

PnP/PCS Configuration

Set PCI Latency Timer (CLK) to 128 (maximum benefit is gained when ASIO latency is below 64 samples)

PC Health Status

Disable CPU Smart FAN Control (if no Fan is used)
Disable CPU Warning Temperature
Disbale Thermal Throttle TEMP

MB Intelligent Tweaker (M.I.T.)

Host frequency at 175 (CPU=1050MHz, FSB=700MHz), core voltage is less than VID.

Set CPU Clock Ratio to 6 (applies to all output rates)

it's better to increase CPU frequency using this multiplier (of FSB) then to increase FSB frequency. cMP² is fully capable of operating at just 840MHz, i.e. 6 x 140.

Set fine control to 0.0 (applies to all output rates)
Disable Spread Spectrum (only availavle with custom BIOS 'F6x')
Enable CPU Host Clock Control
Set CPU Host Frequency (MHz) to 150 (best done with VID at 0.85000V or lower. if system boot is unstable increase to 170)

this gives lower FSB of 600MHz (BIOS should reflect max cpu frequency of 900MHz). some setups will allow for a recommended lowest 140 setting (FSB is 560MHz). cpu load for core 0 will be ~90% for 192k@src145db output. power consumption is reduced.

only use 1 RAM module as this improves stability of lower settings.

Set System Memory Multiplier (SPD) to 2.0 - this sets RAM speed to 300 (2x150)
Set DRAM Timing Selectable (SPD) to Auto

CPU-Z must reflect memory settings: 3-3-3-? @ 150MHz. last setting is RAM specific (kingston hyperx gives 7). reduced RAM reads & writes in cPlay 2.x lowers runtime power consumption. best results achieved when FSB:DRAM ratio is 1:1. although "Auto" setting yields excellent results, manual RAM timings may offer improvements, e.g. using 3-3-3-5 with Kingston's 256MB Value RAM module

Set FSB DeOverVoltage Control to -0.15V
Set CPU Voltage Control to lowest possible CPU VID

lowest setting is 0.85000 when EIST is enabled but depends largely on individual CPU manufacture (as a higher VID may be needed). start at 1.12500V and make sure EIST is disabled (see "Advanced BIOS Features" above). VID lower than 0.85000 can be achieved, e.g. 0.74375. drop VID gradually until lowest cold start VID is achieved. although VID 0.72500 could work, cold-starts would require a CMOS reset indicating instability. power consumption with VID of 0.75000 or lower is less than 20W!

for safe passive CPU cooling, a voltage of 0.95000V or lower is recommended.

Set CPU GTLREF Voltage Ratio to 0.636 (or 0.566) (both very good)

only test this option once above CPU Voltage has been set to lowest stable value. Impact to sound quality is significant and there's no 'right' setting for GTLREF ratio. Depending on CPU voltage, a specific ratio is best.

Perform Save & Exit.