Epox eX5-320S SFF PC

The BIOS: Epox eX5-320S Small in stature, long on options

The BIOS for the eX5-320S looks pretty standard, containing the same menus with options and features that are normally found on full-sized systems.  Anyone familiar with a Phoenix - Award BIOS will notice typical menus such as the Advanced BIOS Features, Advanced Chipset Features, and Power Management Setup, which are used for assigning the boot order of the devices, optimizing the RAM timings and settings caches, as well as determining how the system should react in certain situations, such as a power outage. 

The Advanced Chipset Features provide options which we have seen on other Springdale motherboards, including the full-sized Epox 4PDA2+ v.2, where the memory timings are optimized in order to improve memory performance.  Epox uses what they call Aggressive Memory Mode, or AAM, and there are four settings to chose from: Max, Turbo, Expert, or Standard.  It's really up to the user and the hardware as to which to choose from.  The higher the setting, the greater the chance of instability.  We found that in our testing using Kingston HyperX DDR, we were only able to get the system running while set at Turbo.  Using the 'Max' setting would always cause the system to spontaneously reboot. 

Overclocking Tools Not much to work with

In the POWER BIOS section of the BIOS we found very little to work with for overclocking the eX5-320S.  We could manually raise the CPU speed from the default 200MHz up to 350MHz by simply typing in the desired new speed.  Memory ratios of 1:1, 3:2, and 4:5 are included to make corrections to the DRAM speed so that they aren't run too far out of spec.  However, there is no way to raise either the CPU or DRAM voltages, so we immediately knew that we would hit a ceiling sooner rather than later.  There is also something called the Watch-Dog function that when enabled will automatically reset to a default configuration should the system fail to boot while overclocking, which in this case, we were very thankful for.

SANDRA CPU Benchmark Pentium 4 @ 2.82GHz 12x235MHz

Due to the lack of voltage options, overclocking the Epox eX5-320S didn't require much thought.  We first locked in the AGP/PCI clock to 66/33MHz to ensure that any problems would not arrive from devices on these buses.  To overclock the system, we raised the CPU speed in roughly 5MHz increments while leaving the memory speed at AUTO.  In doing so, the DRAM speed automatically changed from a 1:1 ratio to a more conservative 4:5, so that the RAM never went over the 400MHz it was rated for. In this manner, we were able to only get as high as 235MHz for the front side bus.  At this speed, we were still able to complete benchmarking routines, and did not notice any instability whatsoever.  When we tried to get higher than this speed, the Watch Dog Function apparently cut in, because the system would reboot and reset us back to 200MHz.  At 235MHz, the CPU was effectively running at 2.82GHz, an increase of 420MHz over stock, or 17.5% faster.  We've seen much better overclocking with other Springdales, but due to the limitations of heat dispersal with a SFF system such as this, it's probably best not to push too hard.