Thanks for the link QuietOC. I see where you are coming from now with regard K8 chipsets. I took a look at the article and something doesn’t add up for me with their figures:
Comparison of AM2 & S939 system power consumption from
Techreport. The values below are in Watts and are for AM2 power consumption – S939 power consumption. i.e. + means AM2 consumed more power, - means AM2 consumed less power. Note: Idle is with CnQ disabled.
ATI CnQ +5.1 Idle +14.4 Load +15
nVidia CnQ -5.4 Idle -25.1 Load +6
The differences at idle when disabling CnQ are puzzling: with ATI, AM2 consumes an extra 14.4W, with nVidia, AM2 consumes 25.1W less. To quote Techreport:
‘Keep in mind that because our AM2 platforms are using an underclocked Athlon 64 FX-62, their power consumption results aren't directly comparable to our Socket 939 platforms.’
Whatever the reason these figures don’t add up for me. The power differences under load seem less remarkable, as VRM efficiency and motherboard differences could easily produce those values.