OverclockingUnfortunately, we couldn’t test frequency increases on the P45 with four memory modules because our two motherboards failed before this test. On the P35D3 Platinum, note that it was able to synchronously function up to FSB1560/DDR3-1560 with two modules and up to FSB1400/DDR3-1400 with four. With the P45, Intel only makes the DDR3-1333 support official, something which was already well established in practice on the P35.
For the FSB, with a QX6850 (which is our quad core with the highest FSB wall), we were able to attain 440 MHz (FSB1760) on the P35 at the initial voltage of 1.25V and 470 MHz by increasing the chipset voltage to 1.45V and the VTT voltage from 1.2 to 1.35V. On the P45, at the starting 1.1V we attained 430 MHz (FSB1720) and then 460 MHz by increasing to 1.4V. These were all stable frequencies validated by a 30 minute session of Prime95. Note that the P45 used for this test stopped functioning properly after we tried to stabilize it at 470 MHz.
On paper as in practice, the P45 doesn’t really have anything revolutionary as was the case of the P35 compared to the P965. Of course, DDR3-1333 support is now official (but it was something already effective for the P35) while the ICH only evolves in its standard version.
Actually, it is especially the improved support of PCI-Express compared to the P35 which is of interest. This is either due to new PCI-E 2.0 support or the 16 lanes that can now be shared between two graphic ports. It enables Intel to offer a mid-level chipset capable of properly running two graphic cards independently or in CrossFire. Otherwise, this meant previously having to opt for the more expensive X38 or X48.
So, the P45 will not necessarily motivate you to change your motherboard, all the more so that like all Socket 775 models, it will not be compatible with the next generation of Intel Nehalem processors which will use a new Socket. Moreover, this compatibility is unfortunately impossible given the number of changes on the chipset level in the transition from the Core 2 to the Nehalem: different processor bus, the memory controller moves from the chipset to the CPU, etc.
Finally, like with each new chipset we should keep in mind that it’s the first buyers that will deal with unresolved bios issues. For this reason, some will be tempted to wait for user feedback…or opt for a P35 Express which overall doesn’t have much to fear from the P45. As for us, we were particularly unlucky in this test due to two successive motherboards that could not handle their chipsets being pushed too hard in overclocking. Is this MSI’s fault and related to the motherboard or does this fall on Intel and the fact that the chipset was in its pre-series stage? We can’t answer this question and even if we hope that the latter is true, user feedback on commercialized versions should be closely monitored...