BFGTech, EVGA, XFX Overclocked 7900 video cards have "lock up" issue
NVIDIA have specifically pointed a finger to the cause of the issues being associated with the overclocking settings that BFGTech, EVGA, and XFX use. NVIDIA firmly stands behind their stock core and memory clock specifications for the 7900 series and tell us that they are not seeing any unusual problems with 7900 series video cards that are not overclocked. A little over a month ago, PCPer.com discussed the issue as being the vertex shader unit being clocked too high and NVIDIA stood behind that site on its conclusions.
Well today NVIDIA officially got back to me with an answer to all my inquiries on the subject. The short of it is: the GPUs on the cards that were having problems didn’t have the headroom necessary for the vendor’s overclocked specifications. The two most prominent problem areas were the vertex clock (which remember runs 50 MHz faster than the pixel clock) and the memory clock. These GPU subsystems were running far enough out of spec that the chips were having physical issues with stability; causing the random “freezes” we were seeing. | 