The experimental overclockers and the permanent readers already know that dual core processors core 2 Duo and four core processor kentsfield can be overclocked differently on the same motherboards. We now speak only about the limit of processor overclock on the system bus - as is known, precisely this is limiting many processors with 1066 MHz system bus. It was experimentally established that the processors kentsfield more badly overclock on the system bus, and for improvement in the results it is necessary to go on different setting : for exemple to increase the voltage of GTL reference voltage. Later we were convinced in practice that this voltage can have essential effect on the overclock result for processor kentsfield on the system bus - increase can reach several ten megahertz.
It is necessary to say, that many enthusiasts did not cease to study the voltage influence Of vtt and Vgtlref on overclock for the polynuclear processors intel, and the conclusions obtained to the present day can be presented in interesting facts.
Four core processors intel are overclocked better, if we select the necessary combination of voltage vtt and Vgtlref for each core. The presence of this possibility is determined by the design of motherboard. For example, motherboard on the base of chipset ATI RD600 have the option for regulating voltage in all four cores; therefore the overclock Of kentsfield on the system bus using these motherboard is not very good. These motherboards are inferior in overclock to those providing the possibility to regulate the value vgtlref separately for each cores. Experimental overclockers regulate these voltage with the aid of hardware modifications, selecting optimum values for each core Each core has its optimum value Of vgtlref, which has a positive effect on the overclock result . According to our stats, the correct adjustment of voltage can give increase on the order of 40-50 MHz on the system bus.
In the same way, these modifications help to improve the overclock for dual core processors core 2 Duo on the system bus, only in this case when the voltage values will be selected for the concrete processor individually. Motherboard optimized for overclock of dual core or four core processor, should have such setting for each individual core. Again we repeat these modifications are necessary only for advanced user we have no responsibility for the possible consequences of experiments.