BIOS and Overclocking
We tested the ASUS A8R-MVP with the BIOS dated December28, 2005, which was the latest BIOS version at the time of our writing this review.
The BIOS of the ASUS A8R-MVP mainboard is based on the AMIBIOS microcode, so the Setup program differs a lot from most other mainboards. The options offered are typical enough, though. This BIOS gives you the basic options to configure the mainboard’s devices, but doesn’t offer any extras. We are as usual curious about the overclocking opportunities we have, so here are the overclocking options the mainboard offers to you:
- You can change the clock generator frequency from 200 to 400MHz stepping 1MHz to control the CPU clock rate
- The PCI Express bus frequency can be manually set within a range of 100 to 150MHz stepping 1MHz
- The CPU frequency multiplier can be reduced below the default value, down to 4x
- The frequency multiplier of the HyperTransport bus can be set at 1x, 2x, 3x, 4x or 5x. If this parameter is set at Auto, the multiplier is automatically reduced from 5x to 2x at overclocking
- The CPU voltage can be adjusted from 0.8 to 1.4V stepping 0.025V. The VCORE Over-Voltage option of the BIOS Setup additionally increases the CPU voltage by 0.1V more. Thus, the maximum CPU voltage you can set on this mainboard is 1.5V
- The DIMM voltage can be adjusted from 2.6 to 3.2V stepping 0.05V
- The chipset voltage can be increased from the default 1.2V to 1.3V
- The voltage on the PCI Express bus can be raised from 1.2V to 1.5V stepping 0.1V
Besides these options, the mainboard’s BIOS Setup contains an information screen where you can learn detailed info about the installed CPU, including its core stepping.
Even with these overclocking options available, the ASUS A8R-MVP cannot meet the requirements of advanced overclockers, particularly due to the low maximum of the CPU voltage setting. You can hardly set any records with this mainboard, yet it may suit for “mild” overclocking.
The BIOS Setup offers a wide, but not quite comprehensive selection of settings to configure the memory subsystem:
It’s nice the BIOS Setup supports step-up as well as step-down divisors for the memory frequency: without overclocking the CPU, you can set the memory mode not only as DDR400, but also as DDR443, DDR466 or even DDR500 SDRAM on this mainboard.
The memory subsystem parameters can be set up automatically. In this case the BIOS Setup hides the variety of settings to avoid shocking an inexperienced user. There is one hitch, however. The mainboard will automatically set the Command Rate parameter at 2T in this case to sacrifice speed in favor of higher stability. Our tests prove the mainboard has a reason to do so because of you manually set the Command Rate at 1T, the ASUS A8R-MVP is rather unstable even in its regular mode, not to mention overclocking, and this is a very serious drawback of the reviewed product. So, due to some internal deficiencies, the performance of computers with this mainboard may be about 5% lower than that of similar configurations but with other mainboards.