Just PC / Just 4 PC 425W Power Supply

Hello: long-time lurker, first-time poster here. I just completed my first PC build, and have a question about the case/power supply: it's a Just 4 PC (Just PC USA) JPC GA 755, described at TigerDirect as "Beige Mid-Tower Case with AMD Approved and Intel Pentium 4 Ready 425 Watt Power Supply".

The problem I'm experiencing is periodic random freezes/lock-ups while gaming. Outside of gaming the machine seems to run rock-solidly, and the random nature of the lockups makes me wonder whether the power supply is to blame. I've been monitoring it pretty closely with the "Hardware Doctor" software that came with my motherboard, and I haven't noticed any serious fluctuations in any of the voltages, nor does the exhaust seem overly-warm, but I'm suspicious mostly because it was the only cheap part in the system.

Has anybody tried their luck with one of these Just 4 PC cases/power supplies? I know generics are typically frowned upon, but sometimes you can come up with a winner, and I'd hate to burn money for a new power supply if I should be looking elsewhere for the problem. (I'll post a follow-up message with full system details and a better description of the problem if that's the case.)

Many thanks!
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More about just 425w power supply
  1. On the side panel of the PSU, what brand name does it say, and what are the amps on the voltage rails (3.3, 5 and 12v)?

    Download motherboard monitor 5 and run it, set it to log voltages every few seconds, run your games and check the mbm5 log after it locks up/reboots on you to see if there's any drops in voltages.

  2. I'll have to crack open the case when I get home tonight to fill in the amp/voltage details, but I can tell you that it just says "Just 4 PC" (i.e., the manufacturer) as a brand name. I'll download/use MM5 as suggested; automatic logging while I'm gaming will be useful. I've tried to monitor by Alt+Tabbing back and forth, especially as the action on the screen heats up, but the crashing has been pretty random (and doesn't seem tied to how much the video card is being asked to do). I'm running a GeForce 6600GT, by the way, which requires its own separate power connection.

    If anybody else has had experience with this particular case/manufacturer/PSUI'd be interested to hear about it. Thanks again.
  3. I didn't get onto the computer last night to check the amp/voltage details, but my wife told me about another strange symptom that happened to her: I guess the machine froze up (as usual) while she was running one of the games that came with the GeForce 6600GT. Upon resetting, there was a longer-than-usual black-screen pause between the Windows XP logo and actually starting Windows XP (i.e., showing the profile screen where she selects her name). Typically there's a pause of about 5 seconds between seeing the XP logo and selecting her name, but this time it was closer to a minute. She kept resetting, and it kept happening. That said, once Windows finally was up, she didn't notice any additional problems.

    The only reason I mention it is that when she finally powered the entire machine down and then up again a few minutes later, the long pause had become the typical 5-second pause. Because it required a physical powering-down, does this point to the power supply at all? Or is it just one of those things?

    One last symptom that she reminded me about: about every 10 power-ups or so, the motherboard beeps in the way that indicates that it doesn't see the RAM or that the RAM is bad. Resetting immediately corrects the problem and has never failed. Does this point to the motherboard, the PSU, or is also just one of those things?

    Sorry for the overload of info. that STILL doesn't include any real information about the PSU; I just don't know what's important and what's not. First-time PC builder, don't forget! And not particularly bright besides!

    Thanks again for your eyes and braincells.
  4. You'd better give us a rundown of all your hardware, the state of your Windows Updates and hardware driver updates. Also, and this might have come with your mobo, is the Intel Application Accelerator installed?

    ....WW (5.0)
  5. You should know by now that on cheap power supplies, that label means nothing. As in completely irrelavent, not even close to being factual.

    <font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
    <font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
  6. Well, in case it's still useful to anybody, here's what it says on my power supply label:

    Just PC JPC-425-12V (430W Max)
    Input: 115 VAC/10A Max/60Hz/230 VAD/5A Max/50Hz
    Output: +12V 18A Max / +5V 40A Max / +3.3V 28A Max / -5V 1.0A Max / -12V 1.0A Max/ _5V/SB 2.0A Max

    And when here's what I see when monitoring at idle:

    Vcore - 1.68V
    +3.3 - 3.30V
    +5V - 4.79V
    +12V - bounces between 12.12 and 12.24V
    -12V - bounces between -12.03 and -12.11V
    5VSB - 5.28V
    VBAT - 3.25V

    Here's some system info.:

    System Information
    Time of this report: 3/26/2005, 13:01:55
    Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 2 (2600.xpsp_sp2_rtm.040803-2158)
    Language: English (Regional Setting: English)
    System Manufacturer: VIA Technologies, Inc.
    System Model: KT600-8237
    BIOS: Phoenix - AwardBIOS v6.00PG
    Processor: AMD Athlon(tm) XP 2900+, MMX, 3DNow, ~2.0GHz
    Memory: 1024MB RAM
    Page File: 182MB used, 2281MB available
    Windows Dir: C:\WINDOWS
    DirectX Version: DirectX 9.0c (4.09.0000.0904)
    DX Setup Parameters: Not found
    DxDiag Version: 5.03.2600.2180 32bit Unicode

    Display Devices
    Card name: NVIDIA GeForce 6600 GT
    Manufacturer: NVIDIA
    Chip type: GeForce 6600 GT
    DAC type: Integrated RAMDAC
    Device Key: Enum\PCI\VEN_10DE&DEV_00F1&SUBSYS_21191682&REV_A2
    Display Memory: 128.0 MB
    Current Mode: 1280 x 1024 (32 bit) (60Hz)
    Monitor: Plug and Play Monitor
    Monitor Max Res: 1600,1200
    Driver Name: nv4_disp.dll
    Driver Version: 6.14.0010.7184 (English)
    DDI Version: 9 (or higher)
    Driver Attributes: Final Retail
    Driver Date/Size: 2/24/2005 07:32:00, 3973888 bytes

    Sound Devices
    Description: SB Audigy 2 ZS Audio [9000]
    Default Sound Playback: Yes
    Default Voice Playback: Yes
    Hardware ID: PCI\VEN_1102&DEV_0004&SUBSYS_20021102&REV_04
    Manufacturer ID: 1
    Product ID: 100
    Type: WDM
    Driver Name: ctaud2k.sys
    Driver Version: 5.12.0001.0444 (English)
    Driver Attributes: Final Retail

    The drivers for motherboard, video card, and sound card are latest as available online.

    What I haven't done yet is install MBM5 per the earlier suggestion and log the voltages while I play; it's Saturday night in about 4 hours, so I'll try that tonight. But in the meantime, thanks again for thinking about this. It's very frustrating.

    Obviously, if you no longer suspect the power supply and think my woes should be posted elsewhere, please let me know. Lotsa smart people here.
  7. You have to put a load on the system to see if the voltage fluctuation gets worse. For example, for systems that crash under games, when power is a suspect, I usually load Motherboard Monitor 5 and set it to record the voltages and temps to a text file, at 5 second intervals, 60 entries. Then I run an intense 3D app. That way when it crashes I can restart the computer and read 5 minutes worth of voltage measurements.

    <font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
    <font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
  8. Well, for whatever reason, I couldn't seem to get the machine to crash while I was running Motherboard Monitor 5 as Crashman suggested (I guess the virtual equivalent of the TV Repairman Syndrome). But tonight it finally froze up on me. All I was playing was "Syberia" of all things. As suggested, I have a full 5 minute's worth of readings, but I don't see anything very unusual. Here's what the last reading looks like:

    |Total number of readouts: 196 CPU Speed: 1998 MHz |
    |Running from: 3/31/2005 8:05:54 PM until: 3/31/2005 8:22:09 PM |
    |Sensor | Current | Low | High | Average |
    |Sensor 1 | 0° C | 0° C | 0° C | 0° C |
    |Sensor 2 | 0° C | 0° C | 0° C | 0° C |
    |Sensor 3 | 0° C | 0° C | 0° C | 0° C |
    |Core 0 | 1.68 V | 1.66 V | 1.68 V | 1.68 V |
    |Core 1 | 0.00 V | 0.00 V | 0.00 V | 0.00 V |
    |+3.3 | 3.28 V | 3.25 V | 3.31 V | 3.29 V |
    |+5.00 | 4.76 V | 4.70 V | 4.81 V | 4.78 V |
    |+12.00 | 12.34 V | 12.22 V | 12.52 V | 12.35 V |
    |-12.00 | -12.11 V | -12.03 V | -12.19 V | -12.12 V |
    |-5.00 | -5.19 V | -5.14 V | -5.24 V | -5.19 V |
    |Fan 1 | 0 RPM | 0 RPM | 0 RPM | 0 RPM |
    |Fan 2 | 0 RPM | 0 RPM | 0 RPM | 0 RPM |
    |Fan 3 | 0 RPM | 0 RPM | 0 RPM | 0 RPM |

    I can't say I fully understand what all the numbers are about, but I CAN say that the numbers don't vary much throughout the report. This final reading is pretty close to the first reading from 5 minutes prior.

    How do these numbers look? Do they provide any clues? There's no question that the power supply is cheap, but I'm beginning to suspect that I may be barking up the wrong tree.

    If you'd like to see more readings copied and pasted, let me know.
  9. It doesn't look like a power problem.

    <font color=blue>Only a place as big as the internet could be home to a hero as big as Crashman!</font color=blue>
    <font color=red>Only a place as big as the internet could be home to an ego as large as Crashman's!</font color=red>
  10. Many thanks for all the help! That's one possible culprit I can cross off, at least.
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