The high-TDP quad-core Phenoms don't get enough power on mid-range motherboards

Apr 29, 2008 09:31 GMT  ·  By
AMD's high-end Phenom chips cannot be paired with the mid-range 780G chipset
   AMD's high-end Phenom chips cannot be paired with the mid-range 780G chipset

Advanced Micro Devices has confirmed that its high-end Phenom X4 series of processors are facing compatibility issues when paired with a 780G-based motherboard. According to the company, the high-end quad-core Phenom X4 chips and the 780G chipset are less fortunate matches, given the fact that motherboards cannot deliver the huge amount of power required by the CPU.

"What people have done, mistakenly, is paired a 780G (chipset-based) motherboard with the higher frequency Phenom - the 125-watt Phenom", said Jake Whitman, an AMD spokesperson.

We have written about this issue quite a while ago, but AMD neither confirmed nor dismissed the compatibility issues between the X4 family and the 780G chipset. Users are adopting this hardware configuration in order to squeeze extra computing power, but they usually end up with a computer that sometimes even refuses to start up.

The issue is triggered by the fact that AMD's high-end 9750 and 9850 Phenom processors require 125 watts of power, while the mainstream / low-end parts only draw 95 watts. Such high-end processors cannot work on a 780G motherboard, because it can't deliver the necessary amount of CPU power.

"They've taken an enthusiast-class quad-core part and paired it with a mainstream motherboard", Whitman said. "And not all motherboard manufacturers have tweaked their boards to support a 125-watt TDP", he continued. Whitman also said that the best option would be to use the high-end Phenoms on a motherboard equipped with the 790G chipset.

"We've never made claims that 780G motherboards are enthusiast-class motherboards", Whitman said.

The issue seems to be triggered by OEM builders who want to give extra performance at significantly lower price tags. For instance, HP and Gateway, two of the most committed vendors to AMD's products have only released mid-range systems equipped with Phenom 9100e (1.8GHz) and 9600 (2.3GHz) chips.