Sapphire Radeon HD 5970 2GB Overclock Edition review

"A reference Radeon HD 5970 finds itself clocked lower in terms of both core and memory speeds than the Radeon HD 5870 despite otherwise making use of two full Cypress cores with all of their Stream Processors, texture units, ROPs and so on intact – This leaves us with a core clock speed of 725MHz, coupled 1GB of GDDR5 memory per GPU (2GB in total) sporting a 1000MHz clock speed. The reason for this choice of clock speeds (which also explains the reason for the very modest factory overclocks you might see on some boards, such as Sapphire’s offering discussed here today) is that this is the only way that the Radeon HD 5970 could be kept below the 300 Watt power envelope specified by the PCI Express specification, despite the board itself supposedly having been designed to handle a 400 Watt load – A compromise we may start to see more and more often from graphics boards unless that specification is changed in the near future."

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