Quote Originally Posted by accord99 View Post
At stock perhaps, but the updated Hwbox review suggests Phenom II's power usage grows at a incredible rate when overclocked, to a point where it uses more power than an equally clocked i7 at 3.7GHz.

This would explain why AMD couldn't break 4GHz on air cooling.
original hwbox numbers were all very strange - not sure they have any idea what they are doing.

Intel added thermal envelope protection to i7 because of concern about local hot spots and all the big OC turn it off, because otherwise it shuts the chip down on 4 cores at around 3.5G. Intel also allows full parking of 2 cores to let the other 2 use the thermal capacity, which gives more headroom. The thermal envelope envelope is targeted at 130W.

Looking at screen shots here and on other forums, there seems to be no rapid increase in power on phenom II, at least up to about 4.2G clocks.

It is not reasonable to compare different architectures based on core voltage - power draw with voltage differs even among members of the same family. The best way is to instrument the VRM but that is not easily done. A method that is nearly as good is to use heat rise of a known heat sink. If you have a .1 C/W sink and show a 10C rise, that is a pretty good indicator that the load is 100W. I have several sinks with embedded thermistors at the base. With a controlled ambient air supply that method can be pretty accurate.

Until retail phenom II parts are available, I won't be able to test any by myself, but I will characterize one as soon as I can get it. I am expecting a significantly lower power envelope than i7.

Also, as several posters have pointed out, internal temps are higher than the heatsink contact, often 10C or more. Lower power levels reduce those hot spots - one of the reasons laptop CPUs may run 70C or 80C in 'normal' use. Still, I'm a lot happier with the measured heatsink interface at 50C or less.