ASUS P5K series motherboards
The BIOS of both the motherboards is based on the AMI BIOS
version and has almost identical settings.
In the overclocking section, part of the settings are in
charge of tuning the memory latency timings:
The next important parameter that affects the performance is
setting the memory operating frequency.
The choice of available frequencies is in direct dependence of
the selected Strap:
There is one more parameter that affects the memory subsystem
performance - "Command Rate":
In fact, the current BIOS versions impose certain limitations
upon its use. In particular, in the synchronous mode the overclocked
system does not run stably (in other words, the overclocking capability
degrades). The same holds true for the P5K Deluxe model as well.
There is a couple more parameters to adjust the secondary
timings (sometimes referred to as sub-timings). This is the Transaction
Booster
and the Static Read Control
Enabling these features results in the memory subsystem
performance boost to the detriment of the overclocking capability (in
some cases, to the detriment of stability - especially when the memory
modules run at the breaking point).
Now look at the section to do with the system monitoring.
Both the motherboards display current temperatures of the CPU
and the system, voltages, and the rotational speed of all the four fans
(of five), and offer the feature (Q-Fan2) for adjusting the rotational
speed of the CPU cooler depending on the CPU temperature. For the
processor cooler, there is a separate kit of Q-FAN 2 settings, and for
the coolers plugged in to CHA_FAN1 - CHA_FAN3 there is one kit of
common settings.
Both the motherboards are able retaining all the BIOS settings
in the memory and loading them on demand. The boards support two
independent profiles:
To handle the BIOS, each of the motherboards offers the
integrated EZFlash 2 utility:
The monitoring parameters can be tracked with either AI Suite
(for the basic set of parameters) or with PC Probe II (extended set).
Note that the boards offers support for the CrashFree BIOS 3
feature (restoring the damaged BIOS firmware using a CD or a flash
disk).
Traditionally for motherboards made by ASUS, the BIOS supports
display of the settings in multiple languages (Multilanguages BIOS).
The BIOS also gives access to tuning all the features of
modern processors:
Overclocking and stability
Before we move on to overclocking, let's look at the power
converters. The PWM of ASUS P5K Premium uses a 8-phase scheme in which
there are eleven 561 mkF and one 271 mkF capacitors. The power supply
module of ASUS P5K-E also uses a 8-phase scheme, with the same set of
capacitors. However, the circuitry of the Premium version is somehow
different and is aimed at much higher loads.
Note that on ASUS P5K Premium and ASUS P5K-E some power
components fitted on the reverse side of the board (the way it is on
ASUS P5K Deluxe) are missing.
Now on to the overclocking features.
| Motherboard |
ASUS P5K Premium |
ASUS P5K Deluxe |
ASUS P5K-E |
| Multiplier adjustment |
+ |
+ |
+ |
| FSB adjustment |
within 200 to 800 MHz (1) |
within 200 to 800 MHz (1) |
within 200 to 800 MHz (1) |
| Vcore adjustment |
within 1.1 V to 1.7 V in 0.0125 V increments. |
within 1.1 V to 1.7 V in 0.0125 V increments. |
within 1.1 V to 1.7 V in 0.0125 V increments. |
| Vmem adjustment |
within 1.8 to 2.55 V (0.05 V) |
within 1.8 to 2.55 V (0.05 V) |
within 1.8 to 2.55 V (0.05 V) |
| Vdd adjustment |
within 1.25 V to 1.95 V (0.15 V) |
within 1.25 to 1.7 V (0.15 V) |
within 1.25 to 1.7V (0.15 V) |
| Vsb adjustment |
within 1.05V to 1.2 V |
within 1.05V to 1.2 V |
within 1.05V to 1.2 V |
| Vtt adjustment |
within 1.2 to 1.5V (0.1 V) |
within 1.2 to 1.5V (0.1 V) |
within 1.2 to 1.5V (0.1 V) |
| PCI-E adjustment |
within 100 MHz to 150 MHz (1) |
within 100 MHz to 150 MHz (1) |
within 100 MHz to 150 MHz (1) |
There is a couple more of undocumented parameters to adjust
the CPU power. This is CPU Voltage Reference:
and CPU Voltage Damper:
We could not find out what precisely the CPU Voltage Reference
does. Nevertheless, we noticed some slight drop of the CPU temperature
under load. The second parameter allows avoiding the CPU voltage drops.
This allows choosing the overclocking limit more precisely when raising
the Vcore (since under unstable Vcore the overclocker has to set the
CPU voltage with some margin). But the overclocking efficiency for Core
processors drops at Vcore >= 1.45 V (with air cooling).
Another parameter CPU PLL Voltage is meant for fine-tuning the
power supply of quad-core processors.
Note that the adjustment range in the Premium board is much
higher.
Somehow or other, but we ran all the overclocking experiments
with the disabled CPU Voltage Reference, CPU Voltage Damper,
Transaction Booster, and Static Read Control (let's wait for their
description by ASUS). Therefore, the practical experiments showed that
the boards in question (P5K-E, P5K Deluxe, and P5K Premium) offer the
same overclocking capability which provides a stable operation at FSB
<= 516 MHz.
A few words on the ASUS NOS (Non-Delay Overclocking System)
mode in which overclocking is done on-demand. Simply put, the raise of
FSB speed occurs at the time a resource-hungry application (e.g., a
game) starts up. On closing the application, the system reverts to the
rated frequency.
It allows overclocking the system with AI Suite which includes
tools for overclocking, monitoring, AI Gear, and AI Nap:
 |
Top Stories: |
 |
 |
|
MoBo:
| |
|
|
VGA Card:
|
|
|
|
CPU & Memory:
|
|
