BIOS and Overclocking
The BIOS of our barebone system is based on AwardBIOS v6.00PG micro-code, which has already become a standard for many mainboard manufacturers.
All overclocking-friendly settings are collected in the two pages of the CMOS Setup main menu. The frequencies and voltages are adjusted in the Frequency/Voltage Control, and the memory timings can be reset in DRAM Configuration section of the Advanced Chipset Features page. Here is what you can adjust:
- The CPU frequency multiplier can be theoretically set from 4x to 25x. Quite impressive, don’t you think so? But it is not for nothing that we said “theoretically” here. No matter what value you set over there, the actual CPU clock frequency multiplier remained the same all the time: 11x. The only situation when the multiplier really reduced, was in case Cool’n’Quiet technology got activated and the driver lowered the processor working frequency.
- Fixed AGP and PCI bus frequency. The frequency can be manually set to 66MHz or 75.4MHz.
- The FSB frequency can be adjusted from 200 to 250MHz with 1MHz increment.
- The CPU voltage can be varied from 0.8V to 1.7V with 0.25V increment.
- The memory voltage can be selected manually: from 2.6V to 2.9V with 0.1V increment;
- The AGP voltage can be increased from the default 1.5V to 1.8V with 0.1V increment.
You can set the memory frequency divider. The following frequency settings are available: 100MHz, 133MHz, 166MHz and 200MHz. But even if you set any of these values, it doesn’t mean that the memory will be working at this frequency all the time. When you select any of the above listed frequencies, you basically select the standard proportion coefficient for each of the frequencies. The actual memory working frequency will equal FSB frequency multiplied by this coefficient. For example, if you set this parameter to 200MHz, the coefficient for this working mode will equal 1x. Now the memory frequency will equal the FSB frequency, no matter what FSB frequency you select.
- You can set the memory working mode manually or automatically. The options are: 1T or 2T.
- You can adjust #CAS (Tcl) latency. The available values are: 2, 2.5 and 3.
- You can adjust #RAS to #CAS (Trcd) latency between 2 and 7 with the increment of 1.
Do not forget that we are talking about the BIOS of a barebone system mainboard, so this list of available settings is rich enough. A system like that can barely be overclocked to some significant heights because of the specific cooling limitations. That is why most overclocking friendly settings would hardly be demanded anyway. The available settings we have just discussed are more than enough to adjust the system for optimal functioning.
Here are the results obtained during our overclocking experiments:
Since we failed to adjust the CPU clock frequency multiplier, the entire overclocking strategy was based on FSB frequency adjustments. As for the memory timings, we didn’t even touch them, as they were already configured in the optimal way in the Auto mode. If we tried to adjust them manually, the system either wouldn’t boot up or would perform much slower. When the FSB frequency was increased beyond the indicated value, the system didn’t run stably anymore. Since we came to speak about stability issues, it is important to point out that in case you set the FSB frequency too high and the system wouldn’t start up at all, all you need to do is to shut down the power to reset the settings to their default values on the next boot-up. Unfortunately, this will not work for incorrect timing settings and you will have to Clear CMOS to remedy the situation.