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Instructions for Overclocking

Overclocking an Intel Pentium D 805 processor with the Asus P5W DH Deluxe Systemboard
Tested system configuration:

Intel Pentium D 805
Asus P5W DH Deluxe
Zalman CNPS9500LED-Cu
200GB WD WD2000JB HDD (or equivalent)
Sony 52x CDRW (or equivalent)
2GB Patriot DDR2 PC6400 Kit
550W Mushkin ATX PSU
ATI X1900CF PCIe 512MB Graphics Card
Windows XP Pro SP2

1. Assemble components, and install in a case with adequate ventilation. Front and rear fans are recommended; side panel fan located near the CPU is optional. Adequate cooling of both the CPU and the Chipset/Power regulator heat sinks is critical in an overclocked system environment.

2. Install and test your system using optimal settings before adjusting values manually or selecting one of the Asus Overclock Profile settings.

a.) Install the operating system and verify all necessary device driver support has been installed from within Device Manager. Recommended order is to install chipset first, and then any video, sound, I/O and network drivers necessary.
b.) Install an antivirus product and install or activate a software firewall.
c.) Apply all critical updates.
d.) Perform burn in tests to verify there are no hardware or compatibility issues at normal speeds. Some popular test programs used to determine system stability during overclock testing include:

- Prime95 - calculates Mersenne prime numbers; includes torture test feature and can be configured to run on a specific CPU in a multi-CPU system. (Run multiple copies with affinity disabled and processor 0 or 1 selected.) Running two sessions of Prime95 configured for specific CPUs should maintain CPU load at or near 100% Note: Prime95 needs to be copied into separate directories for each session to be launched.
- StressPrime 2004 ORTHOS by Johnny Lee (based on the StressCPU source code in Prime95.) The current Beta version of Orthos automatically detects a multi-CPU configuration and launches multiple CPU threads. Running Orthos Beta should maintain a CPU load at or near 100%, earlier versions of Orthos required running two copies and configuring each for a specific CPU.
- Super Pi - calculates the value of Pi to a number of decimal places. Run with other software to bring CPU load up to 100%, by itself, Super Pi will only partially load the system.
- Asus utilities, including PC Probe II to monitor CPU core voltage and temperature. Ai Booster may not be stable with all BIOS versions in terms of configuring overclock values, but will also report CPU and system board temperatures, fan speeds and voltage levels. You can also use Windows Task Manager and monitor the Performance tab to observe the CPU load on the multiple CPU cores.

e) Optional: Make a complete system backup. While unlikely, it is possible that system instability from overclocking could corrupt your hard drive image if writing to the drive at the time of a system hang or restart.

3. Overclock the system and test for system stability.

a.) Asus Overclock Profile method.

- Enter the Asus BIOS Setup by pressing the "Delete" key during the power-on startup stage.
- On the "Advanced" menu, select "JumperFree Configuration" and press "Enter".
- On the entry "AI Overclocking" select "OverClock Profile" - For the "OverClock Options" select Overclock 5, 10, 15, 20, or 30%.
- Press F10 to save changes and restart.

• If the CPU is capable of operating at the new frequency, the system should boot and start Windows normally. If the system enters Windows without issue, run your stress test to check stability. If the system hangs or restarts, repeat the process with a lower Overclock Profile setting.
• If the system hangs during the Power On Self Test, the new CPU speed is likely too fast. Power Off the system for a short period and power on again to restart. The Overclock settings should have been reset to factory defaults or the previous successful level. Press "Delete" to enter the BIOS Setup and repeat the process with a lower Overclock Profile setting.

Note: Six different Pentium D 805 processors were tested in this system configuration; all six were able to operate without showing any system instability at the "Overclock 30%" setting.

b.)Manual Overclock method.

- Enter the Asus BIOS Setup by pressing the "Delete" key during the power-on startup stage.
- On the "Advanced" menu, select "JumperFree Configuration" and press "Enter".
- On the entry "AI Overclocking" select "Manual".
- Manual overclock options:
Change only one or two values at a time to selectively identify at what point the system becomes unstable. Overclocking memory or PCI settings can contribute to instability and can increase the risk of data corruption to the hard drive. One suggested approach to overclocking is to increase the CPU frequency until the system just starts to become unstable, and then increase the CPU core voltage until the instability is eliminated. Increasing the DRAM (memory) voltage can also increase system stability, but will also increase thermal output. If the memory does not come standard with heat spreaders, after-market aluminum heat spreaders are recommended. Increasing both CPU core speed and voltage will increase the CPU heat output as well. (The Pentium D 830/840 datasheet shows a maximum core temperature of 69.8° C when drawing 130 watts of power. The 805/820 is designed with a maximum 95 watt profile with a peak temperature of 64.1°

c.) Just changing the CPU frequency by itself is unlikely to result in damage to the processor, however changing core voltage risks permanent damage to the internal circuitry and is not covered under any manufacturer's warranty. Change voltage levels at your own risk!

When AI Overclocking is set to "Manual", options are:

• CPU Frequency - [100-550] (MHz; default is 133 for Pentium D 805)
• DRAM Frequency - [Auto] (default)
• Performance Mode - [Auto] (default
• PCI Express Frequency - [Auto] (default
• PCI Clock Synchronization Mode - [Auto] (default
• Memory Voltage - [1.80-2.40V; Auto] (Maximum Patriot DDR2 voltage is 2.2V)
• CPU VCore Voltage - [1.2250-1.7000V; Auto] (Maximum 805 core voltage is 1.55V)
• FSB Termination Voltage - [Auto] (default
• MCH Chipset Voltage -[Auto] (default
• ICH Chipset Voltage - [Auto] (default

Note: Six Pentium D 805 processors were tested with this Asus system configuration. With CPU VCore voltage at 1.35V and DRAM voltage at 1.90V, three processors failed to be overclocked significantly faster than the 30% Profile (30% = 3.46 GHz). Two were stable at 3.6 GHz, and one was stable at 3.7 GHz. Increasing the VCore voltage to 1.375V with Memory Voltage at 1.9V allowed the one CPU to operate at 3.8 GHz without signs of instability under 100% CPU loads. Finally, all six 805 CPUs were tested at ASUS voltage levels flagged in red as being "high", and approaching the maximum values specified by the chip manufacturers; our results and the settings were:

AI Overclock option CPU #1 CPU #2 CPU #3 CPU #4 CPU #5 CPU #6
CPU Frequency
Memory Voltage
CPU VCore Voltage
(Overclock Speed = freq. x 20)
3.90 GHz
3.90 GHz
3.82 GHz
3.86 GHz
3.92 GHz


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