ATI Radeon 5970 Overclocking: The VRM Temperature Bottleneck
 

In our Radeon HD 5970 review, we ran in to some issues when trying to overclock the card to 5870 speeds of 850MHz/1200MHz. At the time this is something we attributed to the VRMs, meanwhile AMD suggested that it was cooling related, and that we should manually increase the fan speed.

As it turns out, we were both right, we just didn’t have the tools at the time to properly identify and isolate the issue. Late last week we got our hands on a beta version of Everest Ultimate, which added preliminary support for the 5970. With that, we could read and log the voltages and temperatures of the various components of the 5970, and properly isolate the issue.


http://www.anandtech.com/weblog/showpost.aspx?i=657