Board Layout and BIOS of the P4S8X
Cocked, Locked, and Ready to Rock (and
ASUS has a
positive history of making board layout a priority
and it shows on the P4S8X. The board's back
panel is a little unconventional; it sports PS/2 mouse
and keyboard connectors, four USB 2.0 ports, one
serial and one parallel port, an RJ45 10/100 Ethernet
port, three 1/8" mini plugs for audio and a single
IEEE 1394 Firewire connector.
launched the Pentium 4, many prospective buyers were
dismayed that they would have to replace their power
supplies to accommodate the dedicated 12V power
connector. Most newer power supplies are already
compatible with the corresponding ATX 2.03
specification, but for those that aren't, ASUS offers
its EZ Plug feature that accepts a standard 4-pin
power connector. Further, the 20-pin ATX
connector is located at the top of the board,
conveniently located as to not interfere with airflow
around the processor socket. The P4S8X
utilizes a two-phase power solution driven by Intersil's HIP6302 controller.
Officially, the P4S8X supports up to 3GB of PC2700 DDR
memory through its three, 184-pin DIMM slots.
ASUS has equipped the board's BIOS with unofficial
DDR400 settings as well, though. As you can see
from the above picture, an open DIMM slot easily
interferes with the AGP interface, so you'll have to
remove your graphics cards to perform a memory
upgrade. Although DDR333 with aggressive memory
timings performs better than DDR400, we were able to
get the memory bus stable all the way up to 410MHz.
SiS 963 South Bridge, Promise Serial
ATA, and AGP warning light with passively cooled North
The P4S8X is an attractive
offering because of the features ASUS includes. In
addition to the native ATA-133 support offered by SiS'
963 South Bridge, ASUS also includes Promise's
PDC20376 Serial ATA RAID controller, which also
supports an additional channel of ATA-133.
Realtek's RTL8201BL PHY interfaces with the 963 South
Bridge to offer 10/100Mbps Ethernet and the Realtek
RTL8801B PHY performs the same function for IEEE 1394
support. It seems that ASUS is transitioning
away from C-Media's 6-channel hardware audio, opting
instead for the CMI9739A AC'97 6-channel codec.
Moreover, ASUS has added a few extra features on top
of the previously mentioned EZ Plug. EZ BIOS,
for one, allows BIOS updating without having to boot
from a floppy disk, ASUS POST Reporter provides voice
alerts throughout the boot-up process and finally, an
AGP warning light, which illuminates if a 3.3V
graphics card is inadvertently installed.
Award BIOS is straightforward and fairly simple to
navigate. And judging from the submenus, it is
pretty clear ASUS intended the P4S8X to get the
attention of the enthusiast community. Voltage
settings are available for the AGP interface
(1.5-1.7V), the CPU (up to 1.75V), and the memory
interface (2.5-2.7V). Both the front side bus
and memory frequencies can be set independently, the
front side bus being adjustable between 100 and 166MHz
in 1MHz increments and the base memory speed up to
400MHz (200MHz DDR). Memory timings are also
fully adjustable, allowing you to tune whatever memory
you've purchased for maximum performance. Then
again, if you'd prefer to let the machine take care of
that, you can always let the SPD chip arbitrate the
The P4S8X supports AGP 8x,
but that capability must be shared with the
complimenting video card in order to utilize it.
So, if a GeForce4 Ti 4200 is installed, the board
automatically defaults to AGP 4x mode.
Unfortunately, the SiS 648
chipset does not support HyperThreading so there is no
BIOS switch to enable the option. In comparison,
both VIA and Intel support the feature.
sheer number of user-adjustable features in the
P4S8X's BIOS, we were able to poke and prod the board
until we found a reliable overclock. Using a
2.2GHz Pentium 4, we adjusted the Vcore voltage to
1.7V and managed to coax 2.706GHz out of the
processor. At that speed, the PCI bus ran at
31MHz and the memory was operating at 328MHz (164MHz
Overclocking clearly shows notable performance
improvements. The botmatch demo is especially
bound by processor performance, so it is no surprise
that the overclocked platform takes a 21 percent
advantage. The flyby demo exhibits an equally
impressive 19 percent gain, since at 640x480 the
application relies more on processor performance that
it does graphics aptitude.