I had an existing gaming PC that I built from parts about a year ago. It was based on an ASUS P5N-E SLI motherboard (which uses a NVIDIA nForce 650i chipset), with an Intel Core 2 Duo E8400 CPU. This system also had two 74GB Western Digital Raptor 10,000 rpm drives, set up in a RAID 0 configuration. The video card was a XFX NVIDIA 8800GT. It had a Corsair 520HX power supply. It was running 32-bit Windows Vista Ultimate with SP1. This system used 145 watts of power during boot-up and 127 watts of power while idle.
I decided to rebuild this system with a newer motherboard, a different video card and a different hard drive in order to save as much power as possible. I wanted to use this rebuilt system as a “work” PC (to replace an old veteran Socket 939 AMD Athlon X2 4400 system).
I had all of the parts I needed to rebuild the system already on hand. I had an Intel DP35DP motherboard, (which uses an Intel P35 chipset) available. I also had a NVIDIA 8600GT video card (which would be a pretty big step down in performance, but would use less power) available. Finally, I had a single Western Digital Caviar 500GB Green Power hard drive, which I knew would use less power than the two old Raptor drives.
After I swapped all of the parts, and booted into the BIOS setup screen, my trusty Kill-A-Watt meter showed 99 watts, which was a pretty decent improvement to start with (compared to 127 watts). Next, I installed 32-bit Windows Vista Ultimate (since my VPN software does not support 64-bit), and got the various Intel drivers installed, including the thermal management software. After all of this was done, the system was only drawing 77 watts at idle, when the Intel Enhanced Speed Step kicked in and throttled the CPU back to 2.0GHz from the normal speed of 3.0GHz. I was pretty happy with this result.
Speed-wise, the system is rated at 5.6 in Windows Vista compared with 5.8 for the old configuration. The biggest weakness is the 8600GT video card compared to the 8800GT video card. I can live with this, since this won’t be a gaming system.