AMD Phenom X4 overheat revisited: cooling tweaks save budget boards

After AMD was forced to address the potential overheating issues experienced by the higher-speed processors in its Phenom X4 range earlier this week, new testing suggests that workarounds can be implemented so that the 9750 and 9850 chips will work with motherboards not using AMD's recommended 790 chipset.  AnandTech found that, with four low-cost boards claiming support for AMD's 125W processors, modifications including tweaked or aftermarket heatsinks or an additional, targeted 120mm fan would significantly boost stability.  The compatibility claims of those tested had not in fact been validated by AMD themselves.

"Each and every manufacturer, along with AMD, agreed that cooling the MOSFETS [voltage regulator] properly was critical to the successful operation of the board at stock or overclocked speeds with the 9850BE–and to some degree, the 6400+ X2.  This is based on the board manufacturer utilizing a properly developed power delivery system that is designed to handle the 125W TDP processors and in the future, the upcoming 140W TDP Phenoms" AnandTech report

The issue concerns the higher Thermal Design Power (TDP) of the high-end Phenom X4 chips, which equates to greater quantities of heat being created and, if not dealt with, causing system instability.  While the bulk of the Phenom range only produces 95W TDP, further up the range chips output 125W.  AMD is also releasing a 140W chipset later in the year, the Phenom X4 9950.

AMD themselves are also looking at producing lower TDP versions of the chips, with a 95 watt TDP Phenom X4 9750 2.4Ghz first, followed by a new version of the Phenom X4 9850 2.5GHz in Q4 2008.  Their advice continues to be to specify a motherboard using their 790 chipset, rather than the cheaper 780.  DIY system builders and those comfortable with modifying off-the-shelf hardware may be comfortable performing some AnandTech-style tweaks, but mainstream consumers wanting a high-speed Phenom X4 system might do well to hold off buying until the newer, lower TDP versions are more common.

[via Crave]