Advanced Micro Devices on Tuesday confirmed media reports that its latest AMD Phenom microprocessors that have high power consumption may not operate properly on mainboards featuring the company’s latest core-logic with built-in graphics cores. The company said that chips with high thermal design power are not designed to run inside entry level systems and otherwise, the latter are not meant to support the former.

The recently released quad-core AMD Phenom X4 9750 and 9850 central processing units (CPUs) that operate at 2.40GHz and 2.50MHz, respectively, have thermal design power (TDP) of 125W, which is too high power consumption for certain mainboards based on AMD 780G core-logic, which were designed for chips with maximum TDP of about 100W.

“What people have done, mistakenly, is paired an AMD 780G chipset-based motherboard with the higher frequency Phenom, the 125W Phenom. They’ve taken an enthusiast-class quad-core part and paired it with a mainstream motherboard. Not all motherboard manufacturers have tweaked their boards to support a 125W TDP,” said Jake Whitman, an AMD spokesperson, in an interview with Cnet News.com web-site.

AMD 780G core-logic is AMD’s latest chipset that contains built-in integrated DirectX 10-compliant graphics core. Usually mainboards powered by such core-logic sets power entry-level systems that are not usually equipped with higher-end microprocessors. As a result, mainboard makers try to save on CPU power supply circuitry which results in reduced compatibility with certain high-end chips. However, not all AMD 780G-based mainboards are incompatible with higher-end quad-core AMD Phenom CPUs.

Unfortunately, AMD Phenom X4 9750 and 9850 microprocessors are not exactly expensive and aimed at enthusiasts: they only cost $215 and $265, respectively, in 1000-unit quantities. Such price points are usually considered mainstream, not high-end or enthusiast, therefore, quite some people may decide to acquire such a chip along with a platform that features integrated graphics.

Since the vast majority of buyers get their systems from system builders, the latter may simply not offer power-hungry AMD Phenom processors along with more or less simplistic platforms, which not only reduces choice for end-users, but also undermines AMD’s ability to sell more expensive chips. At present Gateway and HP only offer systems with AMD Phenom processors clocked at 2.30GHz or below.