I often mistake my intuition with common sense. In my example, there wasn't any reason to think the Plextor wouldn't be compatible with the ICH6R chipset that is used in my box.
I also believe we have established that the chip most likely wasn't tested, and as such, at least in my estimation, will probably most likely work. I believe it is understood that not every configuration will be tested by each manufacturer, sometimes 'blind leaps' must be taken.
Ultimately it is always up to an individual to practice due diligence before making any purchase. It is also recommended to purchase from a reputable dealer to ensure they are protected should things don't go as planned.
I also suppose the other course could be taken, that being selecting another processor or a motherboard from a different vendor.