![[H]ardOCP](/images/blank.gif){kind=small}
- Date:
- Wednesday, July 30, 2003
- Author:
- Morry Teitelman
- Editor:
- Kyle Bennett
- Google +1
Shuttle SN45G
The SN45G is Shuttle’s answer to the AMD power user crowd. Sporting the new nForce2 Ultra 400 chipset, it’s looking to take on the competition in a big way…
BIOS
For the SN45G’s BIOS, Shuttle chose to implement a Phoenix AwardBIOS. Shuttle customized the BIOS is a few areas to allow for a better overclocking experience with the system.
The Advanced Chipset Features menu contains options for tweaking the performance of various chipset related components, including the CPU and memory subsystems. Changing the system CPU and memory settings can vastly improve system performance, but can also lead to major system stability issues.
The System Performance option determines the operating speed and internal timings between the CPU and the chipsets. With the System Performance option set to Expert mode, all CPU FSB settings become available as well as the CPU Interface option. The FSB Frequency option controls the CPU FSB, allowing a maximum settable FSB of 250 MHz. The CPU Interface option allows for control over the aggressiveness of the CPU bus timings. The bus timings are set most aggressively with the CPU Interface option set to Aggressive. The Memory Frequency option allows for customized setting of the memory speed based on the CPU FSB. The memory speed settings go in a stepwise fashion from 50% up to 200% of the CPU FSB, with the By SPD and Auto settings available for predetermined speed settings. Note that the best performance with an AMD based system is seen when the memory speed is set to the same speed as the CPU FSB, due to latency issues between the memory and CPU buses when running at asynchronous speeds.
By setting the Memory Timings option to Expert, all system memory timing options become user configurable. The configurable memory timing options include active to precharge delay (shown as T(RAS), RAS to CAS delay (shown as T(RCD), RAS precharge delay (shown as R(RP), and CAS latency. Notice that all timing settings, with the exception of CAS latency, allow for an incredibly aggressive value of 1. With all settings listing above, the lower number is more aggressive.
The PC Health Status menu contains real-time statistics for various system voltages, temperatures, and fan speeds for fans connected to the monitored fan headers. The CPU Fan Speed Control option allows for automated control of the CPU fan speed by either preset or user selected temperature thresholds. The User Set CPU Fan option allows for the user to tell the system which monitored fan header the CPU fan is plugged in to, while the Fan Speed Up When CPU Temp option allows for manual setting of the fan speed up temperature.
The CPU Ratio/Voltage Control menu contains the CPU multiplier control options as well as options to control various system level voltages. The CPU Ratio Select option allows for user setting of the CPU multiplier, which when combined with the FSB Frequency option from the Advance Chipset Features menu, gives the CPU MHz speed. Note that the CPU Ratio Select option will only effect the multiplier on a BIOS unlockable processor, such as an AMD Tbred-b or Barton CPU.
The CPU vcore voltage settings in the BIOS are unique to say the least. The vcore voltage is split across two options: CPU Voltage Select and CPU Vcore Above 1.85V. The CPU Voltage Select option allows for a maximum settable vcore of 1.800v. When the CPU Voltage Select option is set to the Above 1.85V setting, the CPU Vcore Above 1.85V option becomes enabled. Through this option, the user can set the vcore to a respectable 2.0v maximum. Unfortunately, the other voltage settings are not as enthusiast friendly. The Ram Voltage Select allows for a maximum settable voltage of 2.70v, adequate for running your memory at rated speed but that’s about it. A higher voltage setting here would go very nicely with the incredible maximum 2.0v vcore voltage and the 250 MHz CPU FSB allowable. The AGP Voltage Select option allows for a paltry AGP voltage maximum of 1.60v which is again enough for normal operation, but not enough for serious AGP card overclocking.