FYI: SMP Athlon Power Consumption

powergyoza · Post by **powergyoza** » Thu Dec 26, 2002 9:30 pm

Using a kill a watt device, I found out that my dual-athlon rig consumes at the very most 250 watts. That's with Win2k is booting up and with both the DVD and CD spinning at full speed. At idle, it's doing more like 210 watts. Network card and sound card weren't really activated so power consumption may go up another 10 - 20 watts. Folding on both CPUs adds another 20 watts or so.

So let's say 250 watts at the very most when the computer is working.

Assuming a 65- 70% efficiency on my PSU, it's putting out about 160 - 175 watts to all of the components. I have 4 sticks of RAM (2 gig), 5 expansion cards (including the AGP), a CD-W + DVD-ROM & 2 HD's. It's not RAID, but it's still a pretty heavily loaded system.

It just goes to show that the power supply companies try to scare us into buying more than we need. I can surely get by just fine with a nice 300W power supply - not the more expensive 400W beast that I have right now.

Anyone else have a power supply bigger than they need?

MGP · Post by **MGP** » Thu Dec 26, 2002 10:16 pm

your findings surely prove why Dell and many OEMs install 250W power supplies even in their top p4 machines...

Alicey · Post by **Alicey** » Fri Jan 10, 2003 9:39 pm

It's kinda a pain though, while 90% of modern PCs will run just fine with a 250W PSU, PSU manufacturers are slowly forgetting low-wattage models, soon you'll only be able to get the 450, 500 and 5347636W PSUs with the latest technology. And latest tech can often be the quietest. So =/

Gandalf · Post by **Gandalf** » Sat Jan 11, 2003 8:25 am

The weird thing is that higher rated (400w eg) psu's have a lower efficiency when they're "only" using 50-100W or so. A regular 150w AT psu is rated 65%, but a new atx400psu will only get 50% at that rate.

TheMuffinMan · Post by **TheMuffinMan** » Sat Jan 11, 2003 8:39 am

I have a 300 watt for my Athlon XP 1700+. 1 CD Drive, 1 HDD, Radeon 9000 Pro, 2xNICs, SBLive!, 2 sticks of 256 and 3 fans. It probably consumes 115-125 watts (delivered) at max. (like UT2k3 over a network, or Bryce 5 rendering burning what's being rendered to a CD in real time)

I could have got away with a 250, but the 300 came with the case. And it's pretty quiet too.

Gandalf · Post by **Gandalf** » Sat Jan 11, 2003 8:55 am

I suppose no one knows of any kill-a-watt like devices that work on European power sockets? (you know, the ones with the *round* holes)