Christian McArdle wrote:
Do you know about CPU Halt and Grant Idle states?

I haven't managed to find any recent figures on AMD/Intel websites,
but they must be on there somewhere.

I've found approximate figures for previous generation processors
which suggest that consumption drops from around 20W to 3W when the
processor is in an idle state. Unfortunately, the source is less than
bomb proof.

There used to be a tool to disable/enable the idle states in some AMD
processors. Temperature sensors built into many motherboards can show that
when the IDLE command was disabled, the temperature of the CPU rose and when
the IDLE command was enabled, the CPU temperature dropped significantly. Of
course, when something was constantly using the CPU (gaming etc) the CPU
temp rose back up and stayed high until the CPU load dropped again.

Just as a pointer, if you're running NT/W2k/XP open up Task Manager, go to
the 'Process' tab and scroll down to the "System Idle Process" process - and
you'll see that generally, its 90% or so idle. As I'm typing this email
I've got loads of IE windows open and OE is checking my email but the Idle
Process is taking about 92-96% of the CPU - and this means that the machine
is only using 4-8% CPU load yet its still displaying the screen and doing
other things.

D