BIOS and Overclocking

We tested Asus P5K Deluxe mainboard with the BIOS version 0311 released on May 28, 2007.

BIOS Setup of Asus P5K Deluxe mainboard is based on AMIBIOS microcode but its structure and looks are very similar to those of BIOS Setups on other Asus mainboards. All sections are very well organized, and it should be very easy to work with even for unsophisticated users. Besides the standard options for configuring expansion busses and integrated onboard controllers that we hardly need to discuss here, Asus engineers as always made special effort to provide their BIOS Setup with a lot of convenient and extensive tools for enthusiasts. This is exactly what we are going to talk about in this chapter of our review.

CPU Configuration section offers all options for work with CPU technologies. Here you can also get the detailed info on the processor installed in your system.

The Chipset section will be of primary interest to those of you who intend to have two graphics cards installed onto Asus P5K Deluxe mainboard. This is where you can set the operational mode for the second PCI Express x16 slot and enable Asus C.G.I. (Cross Graphics Impeller) technology. It first appeared on i965 based mainboards. It allows to slightly increase the performance of CrossFire systems by accelerating the DMI bus (Direct Media Interface) between the chipset North and South Bridges.

However, JumperFree Configuration section is undoubtedly of biggest interest to enthusiasts and overclockers. This is where all the main system parameters are being set including processor bus frequency, memory bus frequency, memory timings and voltages. You can also adjust processor clock frequency multiplier here.

The BIOS Setup of Asus P5K Deluxe mainboard allows raising the FSB frequency up to 800MHz, change the PCI Express frequency between 100MHz and 150MHz, and set the memory frequency using a limited set of dividers depending on the selected FSB speed. If the FSB is set between 200 and 220MHz, the board will offer you only two FSB:Mem dividers – 3:5 and 1:2. With the FSB frequency set between 221 and 292MHz, you will get a variety of dividers including 4:5, 2:3, 3:5 and 1:2. And only if you set the FSB to 293MHz+ you will get access to all dividers supported by Intel P35 chipset - 1:1, 5:6, 4:5, 2:3, 5:8, 3:5 and 1:2.

In other words, if you are building a system on Asus P5K Deluxe, you should remember about two things. First, the mainboard doesn’t support reducing dividers for the memory frequency, and second, it doesn’t support slower memory than DDR2-667 SDRAM even with the FSB set to 200MHz or 266MHz.

Speaking about the memory subsystem configuration, we would like to point out that the board allows adjusting many timing settings:

Besides the timings listed in the table above, Asus P5K Deluxe mainboard allows changing Command Rate. You can set it to 1T instead of the default 2T used by Intel chipsets. You can also see Transaction Booster option among the memory timings. It manages internal registers of the memory controller thus increasing the system performance a little bit. We are going to pay more attention to these particular settings later on.