1. Computer problem? Tech Support Guy is completely free -- paid for by advertisers and donations. Click here to join today! If you're new to Tech Support Guy, we highly recommend that you visit our Guide for New Members.

Please help me calculate power requirement

Discussion in 'Hardware' started by CMaximum, Jul 11, 2009.

Thread Status:
Not open for further replies.
  1. CMaximum

    CMaximum Thread Starter

    Joined:
    Jul 7, 2009
    Messages:
    2
    I'm trying to figure out how many amps at 12v the system I'm building will require, since it seems like the true limit of basically any PSU is the amount of power is supplies on 12v rails. I have a PSU that supplies 17A at 12v and I'm hoping that will be enough. The system is pretty basic:

    ASUS M3N78-EM mobo with NVIDIA GeForce 8300 onboard video
    AMD Athlon 64 X2 5400+ Brisbane 2.8GHz 65W processor
    1 SATA HD
    1 SATA DVD-ROM drive
    May add one or two IDE or SATA HDs and a TV tuner card down the road

    I'm having trouble finding data on how much these devices will draw from the 12v specifically. The CPU isn't hard, since it draws all its power at 12v: 65W/12v = 5.4A. Let's say 6.5A with imperfect efficiency, though I have no idea at what efficiency I should expect the CPU to operate. But what about the rest? In particular, I expect the onboard video to draw significant power at 12v, but I can't find how much.

    Can anyone help? And can anyone suggest a resource for finding this kind of information in the future? When I find power usage information at all, it's usually simply listed in watts, without specifying which rail it's drawn from.

    I did find the following two links in thread:

    http://www.extreme.outervision.com/PSUEngine
    http://web.aanet.com.au/SnooP/psucalc.php

    Both seem pretty useful (if a little out of date), but neither site seems to have good information on onboard video.
     
  2. BG-0

    BG-0

    Joined:
    Dec 31, 1969
    Messages:
    6,922
    The onboard graphics doesn't draw significant amounts of power. You could say 1-2 A on the 12 V rail. It's quite a lot less than what a better discrete graphics card, let's say Radeon 4350 would draw.
    What's the actual model of your power supply? If it's a "Ultra value 500w power supply" then even the underpowered 17 A @ 12V isn't most probably true, rather it's measured as a top peak output at unrealistic circumstances, for example a lot lower ambient temp than what it normally operates at.
     
As Seen On
As Seen On...

Welcome to Tech Support Guy!

Are you looking for the solution to your computer problem? Join our site today to ask your question. This site is completely free -- paid for by advertisers and donations.

If you're not already familiar with forums, watch our Welcome Guide to get started.

Join over 733,556 other people just like you!

Loading...
Thread Status:
Not open for further replies.

Short URL to this thread: https://techguy.org/842212

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice