I was reading this which showed that 2100t and G840 has similar power consumption (within 3W) http://www.xbitlabs.com/articles/cpu/display/pentium-g850-g840-g620_8.html
However I am getting no where close to where they are getting. I am getting 30W at idle, part of the reason might be I am using a Gigabyte Z68 matx board instead of an intel mitx board. I am fine with a few W extra but it seems a bit off.
- Do you have a graphics card installed? (15+ watts)
- Are you giving Windows enough idle time to spin down the hard disks? (5 watts for each drive)
- Do you have your NIC unplugged since boot? (? watts)
- Do you have any USB devices? (up to 5 watts each)
One thing I am uncertain is that when I turn on Resource Monitor, it shows that my cpu frequency is at 57% of maximum frequency. If I use CPU-Z, it shows 1.6Ghz, is this normal? Can't the cpu go a bit lower? In the power settings of windows 7, I set the min cpu frequency to be 5% of maximum. I also have another i5 sandybridge laptop which says Parked on one of the cpu core and the hyperthread core when cpu usage is low. This never happen on my G840, is this normal? Should I see a parked core when cpu usage is low?
That 57% is correct. Your CPU top speed is 2.8Ghz, and all Sandy Bridge desktop CPUs have a minimum speed of 1.6Ghz.
( 1.6/2.8 = 0.5714)