A quick browse of the design guide for the 875P chipset reveal that both the CPU and chipset requires Vcc. That means the 10W-11W I measured on 3.3V line of the 20 pin ATX connector is probably used for the memory and other low voltage components. That leaves ~10W, if I assume 50:50 split between chipsets and CPU that would mean the P4 2.0A draws 54W and the P4 2.4B draws 60W. At least this is closer to intels TDP figures.MikeC wrote:After a long chat with Ralf Hutter, we have come to the conclusion that the dual-12V lines are not the only source of voltage for the P4. RH mentioned that with earlier lower powered P4s, they actually could run without the dual-12V line plugged into the motherboard; just that when you try to put a heavy load on the P4, it tends to get flaky. They were intended to be auxiliary 12V lines -- ie, a way for the board to get more juice directly when needed.
Hence the widly varying results...
I am sure there is a tech doc somewhere on Intel's site that would give precise info on this, but there's no way I'm going to dig through them right now.
It could also be true the dual 12V line is used to power other components on the motherboard such as the VGA.
Anyway, time to draw this whole excerise to a close - I need to get my computers back to folding otherwise hayesdb will start to PM me due to the drop in points .