NoNoBadDog! said:
However you slice it or dice it, it is still wrong to claim that a 250
watt PSU can power 400 Watts of hardware. Amperage is important, and a
rock solid 12 volt rail is essential, but you still cannot run nearly
twice the wattage, no matter how "good" the PSU is.
You have a long, long way to go to defend your claim. Math is on my side.
Electrical engineering is on my side. If you can definitively demonstrate
a single brand, make or model that will power nearly twice it's rated
load, and do so reliably, and do so without extreme temperature
fluctuations...well you get the point. To claim that *ANY* 250 watt PSU
can power 400 watts of hardware is just plain wrong. If so, why would it
be rated at only 250 watts?
You need more than manufacturer specs to back up your claim.
Bobby
Bobby. I've owned four Shuttle XPC's with no more than 200 or 250W PSU's
over the last several years. Currently I am running in one rig:
Opteron 175 (o/c'd to 2.42GHz)
GeForce 7900 GT
WD Raptor 10,000 RPM SATA HD
2x1GB Corsair XMS DDR500
Creative X-Fi
DVD-RW
And was running a similar setup in an AGP rig with an ATI Radeon X800 XT
Platinum with no issues for well over a year and a half.
The PC40 PSU is rated at 250W. It has 16A along each 12v rail. Check out the
specs here:
http://www.zipzoomfly.com/jsp/ProductDetail.jsp?ProductCode=150998
Total peak draw from the wall to the PC is 190W, but hovers around 160-170
during intense gameplay. Take into account the efficiency of the PSU (about
72%) and its running at about 135-140W draw from the system.
Higher wattage rating from video card vendors only ensures it is carrying
enough current to run the video card. Now video card manufacturers are
specifying the total required amps on the 12v line, and not so much the
Wattage. Keep in mind too that the Shuttle SFF PC's have limited room for
expansion, so you are limited in the number of peripherals that you have
installed, limiting the drain on the system. Your biggest power consumers
are the GPU and CPU. Since you're allowed one PCI-E (or AGP), one PCI, two
3.5" drives, one 5.25 inch drive, and two SDRAM slots, it's highly unlikely
you'll tap the full power requirements of the PSU.
I read somewhere, can't find it at the moment, that did a good article about
PC power consumption. Even a standard high-end ATX PC drew no more than
about 220W from the wall. You just need a high quality PSU that is rated for
All that being said, if the system had 10 hard drives, four DVD drives, six
PCI peripherals, eight gigs of ram, and an SLI setup, that might require
450W of total power, probably more like 300-350W, no you could not run off a
250W PSU. However, you could probably run that off a higher quality 450W PSU
than a cheapo 650W PSU. Keep in mind too that many PSU's are rated at a
certain temperature. Many rate the power at 20c (or room temp), and the
power greatly reduces with increase in temperature. We all know that PSU's
don't run at 20C, more like 45C.
I'll stop here. It's more complicated than you think.