ASUS P5K vs. P5B – Consumption, Overclocking
Consumption
Before we more closely address overclocking of the P35 compared to the P965 Express on two leading ASUTeK motherboards, the P5K Deluxe and P5B Deluxe, the power consumption of these two cards was measured. We used an ammeter to take readings on the different lines of the ATX block. This allows us to do away with processor consumption, which is fed by the ATX12V, and part of that which feeds graphic components on the six pin PCI Express outlet. Measurements were done with 2x1 GB of DDR2-667, an E4300 in rest and then in load with Prime95, and a Radeon X1950 Pro:
As you can see, figures are comparable.
Overclocking & FSBHere we started with overclocking the chipset with two different CPUs, a Core 2 Duo X6800 and Core 2 Quad Q6600. We only give you the frequencies validated with two to four sessions of Prime95 for 15 minutes.
On the P5B Deluxe, we reached 510 MHz of FSB with the X6800 without touching the chipset voltage, and then we attained 530 MHz in going from 1.25 to 1.45V. On the P5K Deluxe, the 530 MHz was reached with the starting voltage, 1.4V for the chipset and 1.7V with the CPU PLL setting, which allowed going up to 540 MHz. We should also note that on the P5B Deluxe we had to go to 1.45V to reach 430 MHz in order to not have a PCI Express slot configured in x1 instead of x16. We didn’t encounter this problem with the P5K Deluxe. Like on the P965 with high FSBs, an active ventilation (or watercooling) of the chipset would be desirable and for us we did this starting at 500 MHz.
With the Q6600, results are even better because while the P5B Deluxe limited us to FSBs of 340, 360, 370 and 380 MHz with chipset voltages of 1.25, 1.45, 1.55 and 1.65V, on the P5K Deluxe we were able to obtain 470 MHz with starting voltage and 480 MHz in pushing the chipset to 1.55V and the CPU PLL to 1.7V.
Performances & FSBFrequency isn’t everything in the domain of FSB, as the P5B Deluxe is well known for using much higher latencies on the chipset level as soon as we go to 400 MHz. Is this the same for the P5K Deluxe ? To find out we carried out various performance tests always at 2.67 GHz, but in FSB1066 (266), FSB1333 (333) and FSB1777 (444). You should note that contrary to the P5B, with the P5K the modification of the processor ratio is found in the JumperFree menu, which let’s us avoid going between two menus for this adjustment.
While P5B performances in FSB1777 are poor, frequency is not enough to compensate for latencies that are too high in relation to FSB1333. The P5K doesn’t suffer from this problem and therefore has performances that are 3 to 4% higher.
Frequency & memoryWe end this test with a test in increasing memory frequencies with a FSB:DDR ratio of 1:2, carried out with 2x1 GB of PC2-6400 Crucial Ballistix Tracer configured in 5-5-5-15 at 2.25V, and then with 4x1 GB of the same type of memory.
On the P5B Deluxe maximum frequencies are 590 MHz with two memory modules and 570 MHz with 4. Increasing the chipset power did not have a positive effect on the increase in frequency.
On the P5K Deluxe, at the starting voltage we are at 600 MHz with 2 memory modules and 550 MHz with 4. The increase in chipset voltage did not allow going any further with 2 memory modules, however, with four we obtained 560, 580 and 590 MHz at 1.4, 1.55 and 1.7V, respectively.
