INightmare's ideas

I'm running a server in my room and one day got curious, just how much power does the thing consume. Got a power meter from a friend and started testing.

• CPU: AMD Phenom 9600 Black Edition (4 x 2.3Ghz)
• GPU: NVIDIA GeForce 7025 (the monitor was not plugged in)
• RAM: 2 x 2GB DDR2 800Mhz (running at 533Mhz I believe)
• Motherboard: ASRock N68C-S UCC (nForce 630a chipset)
• Additional cards: VIA Rhine III network adapter
• HDD: Samsung SATA drive
• Power supply: 420W

Server runs Debian 5.0.

Booting up showed around 90W of power consumption, when it was done loading it dropped to 63W. That's how much it uses when idle and running all 4 cores at 2.3Ghz.

Ran a 4-threaded application (a continuous loop which performs some simple math). All cores ran at 2.3Ghz. After I tested it with 4 cores I began turning cores off one by one. Here's the result:

Turning off cores when CPU is idle didn't help much. Went from 63W to 61W.

1 core: 73W
2 cores: 82W
4 cores: 102W

So one core takes ~10W of power when running at 1.2Ghz and full load.

So how much does the scaling help? Going from 1.2Ghz to 2.3Ghz adds about another 10W per core.

AMD+NVidia platform is amazing. Drawing 62W when idle... WOW. My Asus F3Ka laptop with Turion TL-60 (2x2Ghz) uses 44W on wifi, full brightness when idle at 2x800Mhz and 80W at full speed. The difference isn't all that big. What can I say, AMD did a fine job.