3.3v is Fluctuating a lot

By duomaxwell ยท 14 replies
Jul 2, 2006
  1. my PC:
    mobo: kt3 ultra
    cpu: Athlon 1.15GHz
    GPU: Radeon 8500
    ram: 1.24 gig

    My pc is roughly 4 years old and i have not had any problems out of it untill now. I recently upgraded my ram from 512 to 1.24g (1 512 chip) and windows is showing that i indeed have 1gig of ram. I have had 1 gig of ram in my pc before, but i removed and sold one of the chips awhile ago. The problem is when i play a game (world of warcraft) a software called PC alert 3 (system monitor) sets off a alarm ever so often when my voltage (3.3v) is either going over (3.63v) or under(2.97v). All other voltage are staying well with in safe parameters. My pc does not crash or have any problems other then the system monitor setting off an alarm. What could be going wrong? or is it nothing to worry about?
  2. DonNagual

    DonNagual TechSpot Ambassador Posts: 2,406

    Hello and welcome to techspot!

    Keep in mind that software readings of PSU voltages are calcutations of the voltage and not the actual voltage. Software readings are unreliable, however they also shouldn't be ignored completely.

    Take a look in your bios for a second opinion (likely it will read exactly the same).

    But the only way to be certain would be to get a voltmeter (they are cheap at radio shack) and test that way.
  3. KingCody

    KingCody TS Evangelist Posts: 992   +8

    Hi and welcome to techspot :)

    if your voltage is indeed fluctuating that much then you need a new power supply.

    most power supplies regulate voltage within +/- 5%. however if the power supply is a cheap/generic one then it's not unusual to see the voltages go way up or down when the system is taxed.

    but before you start worrying, you should realize that often times software based monitors are not very accurate and it may be simply displaying inaccurate information.

    1. what brand is your PSU?

    2. do you have (or have access to) a digital multimeter to test the actual voltage as the system is used?

    EDIT: don beat me to it, but you get the idea. good luck :D
  4. duomaxwell

    duomaxwell TS Rookie Topic Starter

    Thanx for the quick response!

    how would i test my pc using a voltmeter?
  5. duomaxwell

    duomaxwell TS Rookie Topic Starter

    my psu is a raidmax

    i'm wondering if the new ram i installed could be defective in someway. because that is when the problem started.
  6. duomaxwell

    duomaxwell TS Rookie Topic Starter

    my bios gave me this info, which differs from the system monitoring software

    my software gives me
    vcore => 1.78v
    +5 => 5.03v
    3.3v => 3.25v
    +12v +> 11.80v

    my bios gives me

    vcore 1.776v
    +5.0v 5.140v
    +12.0v 11.923v
    -12.0v -12.153v
    -5.0v -5.077v
    battery 3.376v
    +5vSB 4.872v

    i did not see a 3.3v in the bios...
  7. KingCody

    KingCody TS Evangelist Posts: 992   +8

    that's pretty simple. on a 4 pin molex connector, the yellow wire is +12v, the red wire is +5v. to test the 3.3v rail, you can use either of the 2 orange wires on the 6 pin "aux" connector, or on the 20/24 pin ATX connector. the ground for any of those readings can be a black wire, or the case, or a screw holding the PSU, etc.

    well that's a problem in itself. raidmax is a bad brand. consider yourself lucky to have gone 4 years before a problem occured. according to this guide here , raidmax is on their list of unscrupulous power supply companies.
  8. duomaxwell

    duomaxwell TS Rookie Topic Starter

    thanx for all the help everyone! I'll be checking my power supply and will be more then likely buying a new one.

    Thanx again
  9. nork

    nork TS Maniac Posts: 306

    Here's more info for you on power supplies:
    Here are lists of good and bad power supplies:


    troubleshoot power supply with multimeter:

    atx format:

    Also, you can google info on how to test your own power supply with a multimeter that you can pick up for about $10 US. If you go to techrepublic.com there is a very good tutorial there with pics, as noted above. You can use screen capture to make a copy of it. You have to register but its free, a great site, and they dont bug you.

    example of good but low-priced power supply (if its still there). Look for Fortron, Antec, enermax :

    This is the $25 to $50 range.

    If its not there then just go to newegg, then to power supplies, then ask for a list of power supplies in a certain price range.

    As already stated, poorly built power supplies (ps) may run for a while but then they die before they should. The worse thing is that when they do die, or when there is a power at the wall issue, these ps's not only go bad but they take other parts of your pc with them. When a good ps gets hit bad by power issues at the wall, for example, they have circuitry inside them to prevent problems and if they do go their circuitry is built so that your other pc parts dont get damaged!
    Raidmax, sorry to say, is not a good power supply. You have done well to get by with it.

    On final item you might consider. Everyone should have a UPS (uninterruptible power supply) connected between their pc and the wall. They can be had these days for as low as $50 or less, a very very good investment, at least as important as a good power supply, maybe more important. Too bad the pc companies dont tell you about poor quality power supplies and UPS's!
  10. luvhuffer

    luvhuffer TechSpot Paladin Posts: 443

    Don't be sticking multi meter probes into connectors! A mistake can ruin your whole system. Unplug every lead from every piece of hardware till nothing is attached. Go to the 20 pin connector and find the green wire. That is the switch. Jump it with a black wire using a small piece of wire stripped on both ends. That will power up the power supply. Then go ahead and check your voltage. 3.3V wil be the orange wire. A point to note. The power supply is the only piece of hardware in that case capable of destroying every other piece of hardware. It's 4 years old. Trash that thing and go get a decent one. Minimum 20amps on the +12V line. More is better. Mine has 30A. Get a revision 2.0 or higher. Think about upgradability.

    Nork. Sorry if I just repeated what your links say. It's hot and I'm lazy.
  11. nork

    nork TS Maniac Posts: 306

    To duomaxwell

    The page i gave you is no good now, here is a new one. There you will find forton, Antec, Enermax power supplies. Make sure you get the minimum you need and if you want you can get a power supply that will work on your next pc you build as well. If so, then get a power supply with a 20 + 4 pin connector.


    luvhuffer, no problem, thanks for the consideration.
  12. duomaxwell

    duomaxwell TS Rookie Topic Starter

    Thankyou for all the advice guys.

    I do have 1 other thing to add though.
    I just pulled out the new ram stick i put in my pc, and the voltage fluctuations have stoped. what does this mean?

    remember the only time the voltage fluctuates is when i'm running a video game or other major app. which i'm running the game and there are no fluctuations, but of course my game is running slower now.
  13. KingCody

    KingCody TS Evangelist Posts: 992   +8

    it could mean that your PSU is at full capacity, and adding that extra stick of RAM draws too much power.

    this again comes down to the PSU being low-quality. the voltage regulation circuit (as well as all other circuits) in a cheapo PSU do not do what they are supposed to when the system is taxed.

    It would be safe to assume that if you bought a good PSU, the unreliable voltage regualtion would stop. replacing that raidmax PSU is highly recommended whether or not it is the cause of your problem
  14. duomaxwell

    duomaxwell TS Rookie Topic Starter

    thanx a lot king and everyone else.
  15. duomaxwell

    duomaxwell TS Rookie Topic Starter

    I just noticed that my 3.3v is jumping up and down again (with the new ram stick out and not running anything but this website). So i would say everyone Is 150% correct.

    Next stop Newegg.com!!!!!!!!!!!!!!!!!!
Topic Status:
Not open for further replies.

Similar Topics

Add your comment to this article

You need to be a member to leave a comment. Join thousands of tech enthusiasts and participate.
TechSpot Account You may also...