Connecting to mobo/cpu

I'm troubleshooting an issue, and want to try my mobo with another PSU. The only one I have is a rather old one with built in cables and only a 4 pin plug to go to the upper CPU plug part of the Mobo, whereas the motherboard (msi 870a-g54) has 2 4 pin plugs for a total of 8. Does that mean I'm out of luck using this PSU to test? Or will it run with only one of the plugs plugged in?
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  1. it will run on the 4pin, it should fit into the 'bottom' fourholes in the socket, its formfit so 'cant' go wrong :P
    only possible issue is the cpu may require more power i.e. if overclocking heavily and need you to use the full 8pins, in which case yes, new psu time :P
  2. thanks! i'm not overclocking so that would be fine. unfortunately my gpu requires power and this batty old psu does not have the connector for that, so i'm out of luck anyway :(
  3. you can try a molex>pcie adaptor like, or maybe its new psu time, your call man :)
  4. The 8 pins are for running different aspects of the motherboard. Unfortunately 4 of the pins are required for running power to the pcie lanes so it wouldn't have worked anyway. What are you trying to troubleshoot on your board? Or are you troubleshooting your PSU?
  5. i suspect it's the mobo, but i want to rule out it being the PSU, since I'm onto my second mobo with the same problem.
    Basically whenever ethernet cable is plugged in the audio hiccups and glitches.. kinda looks like it affects video as well. I've tried it breadboarded out of the case, in different rooms, with different soundcards, with an pci network adapter, with the network cable just plugged into a laptop running on battery... all these situations still yield the same result. I was convinced it pretty much had to be the motherboard based on that, MSI seemed to agree, so I sent it back with an RMA which took 1 month (!!!) to come back.. and still had the same problem. So before I send it away again I want to make sure replacing the motherboard actually has a chance of fixing my problem... so want to try booting the system with a different power supply, but the only one i have is that old one that won't seem to do the trick

    (the power supply that's meant to be in there is a cooler master silent pro 700 w)
  6. Based on that I would have to agree with Motopsychojdn. If it has been checked/repaird by MSI and it still does the same thing I'm thinking power supply also. If your psu has the 4+4 pin connector I would try unplugging one of the 4 pin connectors and see what happens. Worse case is there just isn't enough power to start the board. If it starts and you have the same problems then you lost a rail on the psu. Since it will start up I would download, install and run OCCT. I would do a small test on the cpu tab and watch your voltages (with all your power plugs plugged in for this test) Watch them to see if they drop off. If you run the test for 10 min and it completes it will give you a graph on how they did. If it aborts the test due to power fluctions (as long as it doesn't bsod on you), again, it will tell you why it was aborted. I wouldn't try the power supply test. If it is faulty it might blow up on you. It is a stress test not a trouble shooting test. Try those before buying anything. Also, if you have a small computer shop around they might be able to actually test your psu for you! Give those few things a try and let us know what happened.
  7. ok.. that's helpful! but i'm not totally clear on what I should do.. should I ignore the old PSU I was going to run and just try to run some tests on my current CoolerMaster one?

    what is the purpose of unplugging one of the 4 pin connectors?
  8. Yes, I would ignore the old PSU at first. Work with the coolermaster first. Download and run the OCCT and see what happens. After that try unplugging one of the 4 pin connectors to see what happens, (turn everything off and unplug the power source first), After you unplug it turn everything back on and see if the mobo powers up. If you get video you will be able to try your old PSU. If not then we can try this. Do you know how to run a jumper across your psu 24 pin connector so it powers up without being plugged into your mobo? If not check this. We can try using both psu's at the same time. Plug your old psu into the mobo 24 pin connector, then plug the one 4 pin connector into the mobo. Now, run the jumper wire in the coolermaster (cm) 24 pin connector as described in the video and plug the other 4 pin connector into the other 4 pin slot on the mobo. Now you can also plug the vid card connector in from the cm to power the video card. Make sure you don't touch the jumper wire while the psu is plugged in and make sure it's not touching anything that will short it out or electrocute anybody/thing. After you have done all this you can turn on both psu's. This should start your board with at most the same problems you were having to begin with (hopefully will be less). Check to see if the old problems you were having before are still there. Are any of them working correctly now? The purpose of this is to take away the demand from the cm and put it on the old psu. If your not using as much of the cm psu and some things have improved then I would replace the Power Supply Unit. If there is no change then there's a good possibility that we just wasted your time but trouble shooting is ofter like that. Try those few things and see what happens. Did this answer your earlier question about how to proceed?
  9. Ok... I did a CPU test with OCCT.. I'll put up the png it outputted.. don't really know what I'm looking for there tbh!

    My old power supply I don't think is gonna work as is at all bc my GPU needs a power connector and this terrible old thing doesn't have anything that will plug into it! I may be able to find an old video card or another power supply somewhere though. Or that really complex procedure you mention.. but then the CM is still involved.. probably best to get it out of the equation entirely, right? Even if it is just powering the video card...
  10. If you scroll through the graphs you will see one for the 3.3 volt and one for the 12 volt. Just wanted to get a look to see if they fluctuate or if the test aborts due to fluctuations.
    Yeah, it is kinda complex but it doesn't cost anything but time. But yes, the easiest way is to just try a compatible psu. Changing out the video card might help as it will draw less power but that only affects 1 rail and doesn't do anything for the 3v and 5v source. No computer shops around that might test it for you? That's actually your best and cheapest way to go. Otherwise you'll have to buy another psu. $80 here if you don't see anything else you like. I don't see returning the mobo as viable but if it's still under warranty, don't cost you anything and you can wait forever I guess it's better than nothing. Sorry I couldn't be of more help.
  11. Hey no need for apology, you have been really helpful! I may be able to find a PSU from a friend, too. I don't know any area computer shops too well, but I may have a look around; I never know how much to trust those places
    I already swapped out the motherboard once, so that's not looking super viable.. but everything still should be under warranty.. I bought these parts just in june/july

    the only graphs occt gave me was cpu 1-4; maybe there are some options i need to toy around with.
    edit: i see in the options some options for voltage but they're all disabled and the only option is disabled.. maybe something my mobo doesn't have?
  12. What PSU do you have anyway? Make, Model, wattage, that sort of stuff. Is it still under warranty also? You might want to send that back for an exchange or repair. Did this board used to work and then you started having trouble with it? Or is it a build that you could never get to work correctly? I should have asked these questions to begin with LOL. If your running with a small or underpowered or even a junky built power supply it just might not be enough to power everything. That would be funny, well not the junky one since you picked it out. Well ??? Let me know whatcha got. It would actually be great if that's all it is cause then we can fix it.
  13. it's a 700w Cooler master SilentPro.. actually my whole parts list is here
    So the power supply should be good enough. And it has a 5 year warranty so it's still under warranty...
    The problem I'm having.. it's been going on mostly as long as I've had the system I think. I can't remember when it exactly started/when I noticed it, but it wasn't long after things got running. It took me a long time to narrow things down because it is a pretty odd problem. At first I just assumed it was my speaker cables or this external audio interface I have, but I gradually isolated things out.. eventually realized that it got better and reboot and took a while to manifest after rebooting, and eventually swung into full gear testing it in different rooms and things.
    The weeeirdest thing is this: I take my ethernet cable out of the router so it's not powered, but left into the back of my computer... the glitching stops. I take the other end of the cable plug it into the ethernet in on a surge protector. Take another ethernet cable plug it into the ethernet out on the surge protector, and plug the other end into my laptop that is running on battery and not hooked up to anything, and it starts glitching again. My friend feels this shouldn't be possible since it's not even a crossover cable. But I saw it happen!
  14. What happens if you take the S.P. out to the router again?
    Sorry for absence in answering, I work nights :)
  15. sorry what's S.P. here? i don't quite get what you're asking :p
  16. surge protector,

    your glitching if pc goes straight to router yes?
    but not if you take it and go through surge protector,
    my idea was run it through surge protector to the router, see if that helped at all
  17. ah like the network cable? I have tried it going from the router to the surge protector to my pc.. that's without lugging my tower upstairs to put it next to the router for now. I did try it directly in from the modem before I got the mobo replaced, though.
  18. Alright. I have my computer hooked up via another power supply, with a different video card as well and only one hard drive and no cd rom, but still in the case w/ the other power supply sitting on top of everything. It's still doing the glitching, albeit much less frequently. much much less. it's almost bearable. but it's still doing it.. which is really weird.
    is it the motherboard then? or a problem with the house's electricity? though there've been many computers plugged in here before this one that never had a problem...
  19. could be your house supply, wierder things have been known :) the other pc's you've had in there may not have needed as much juice maybe?
    if you can get a 'known good' psu from a mate maybe to test out, it might confirm the theory.
    or take your rig round their house,
  20. There's no simple way to test house power huh? I know if I had a battery backup i could try that, but I do not. Dragging my comp to someone else's house may be kind of complicated, I'll see if I can figure something out. And what if it still does it there? Go back to blaming the motherboard despite being on the second one?
    I guess it could be a combination of a fairly substandard motherboard and some household electrical anomalies?
  21. its possible the mobo is on its way out, but to confirm that you'd want to make sure its not a power issue, you may get a new pc only to find its not the pc's fault,
    I'm not sure (other than getting an electrician out) how you would assess your house electrics though sorry :(
  22. This is a brand new motherboard sent by MSI because of the same problem.. which is still continuing. I'd hope it's not on its way out after a week!
    I am going to try and bring my tower over to a friend's house tonight though and see what happens, though
  23. ok, I'll check back in the morning when I get in from work, good luck man
  24. I hooked up comp at buddy's house.. after about 3 or 4 hours it didn't seem to be doing it, but since it can take a while to manifest, I left it there overnight. We will see.
    Also got a call from an MSI technician today who seemed pretty knowledgeable. He thought of some things to try... doesn't see how it could be the motherboard, but not sure what it would be. No solution, but redeemed my opinion of MSI a chunk for sure.
  25. Always good to hear positive feedback about companies :)
    let us know how things turn out at your mates house, and if any of the tech's solutions help too :)
  26. Bit of a delay.. life is busy! But I thought I'd keep you guys up to date .
    It turns out it works fine at my friend's house.
    It also turns out that it's possible many of the outlets down here are not grounded properly/at all.. being a 50s house and such. Based on what's happening, that seems preeettty likely to be a problem. I'm waiting on a friend who has a tester you can plug in and doublecheck if an outlet is grounded.
    I mean.. there's been many other computers here that worked with no problem.. so it's unfortunate that this one seems so sensitive! Maybe that's a general comment against the motherboard in question.. not sure.
    But right now I'm generally keeping the internet unplugged unless I need something, and waiting to have a chance to see if there's a grounded outlet in this room (and kinda assuming the one it's now plugged into isn't)
  27. Cool, at least you now know your pc isn't the problem :)
    bad news is house electrics cost more lol :(
  28. yeah...
    it's odd that i never had this problem before with other PCs hooked up the same place. So.. the PC is partly responsible still!
    It is possible some of the outlets are grounded, but I have yet to doublecheck
  29. hope it goes well for you man,
  30. Well...
    It turns out the outlets really ARE grounded.
    So at this point I really don't know wtf.
  31. Ok, recap:
    House power ok,
    Mobo is a replacement unit,
    You havent tested with another psu yet though if I'm correct?
  32. Nope.. tested with a different PSU and it still did the same thing!
    tested at my friend's house and it didn't seem to be doing it after almost 2 days.
    House power.. is at least grounded.

    Right now I'm trying a different power cable from the surge protector to the PSU (one little thing I hadn't yet tried swapping).. and it's been ok after about 30 hours, I think. They're may have been a few clicks, but not totally sure. It's generally behaving itself so far at any rate.

    I feel like using a different power cable may more reset than solve the problem, and maybe that's what happened sorta at my friend's house (though that was using the same cable I'm pretty sure, but it was unplugged for quite a while in between). I am going to have to leave this on longterm to be sure.

    edit: pretty sure it's doing it again, but still much less than it had been.
  33. Unless anyone else can come up with any ideas,
    I'm stumped lol, I know it doesn't help you any,
    See how it goes trying new cables like you said,
  34. Yeah.. the new power cable .. it's still doing it for sure. But definitely less. Whatever that means.
    I'm about ready to blame ghosts at this point.
    Though the fact that it took so long to do it with this new cable makes me less totally sure that it wasn't doing it at my friend's house.
  35. so i'm not really sure that the house has anything to do with it, the outlets are definitely grounded.
    i think it is affecting video playback as well as audio, so could be something overall with cpu processing that's hiccupping.
    i had that one stint where it barely did it.. the resurgence may have been due to using my external sound interface, but I've not used it for several weeks and it's still doing it.

    i'm wondering something i never thought of before.. we have an older big tube tv on the other side of the wall that's kinda crappy.. it doesn't degauss properly.. as the colours get out of whack quickly. that's a pretty big field from that i'd imagine.. any chance that's contributing? haven't noticed a pattern with tv usage particularly, but it's one of few things i can think of. (even though it does have the problem in different rooms occasionally.. i think the effect takes a while to dissipate or something.)
    right now i'm sorta trying to figure out how to reproduce that bit where it didn't do it for a few days.. that was cool. but no luck so far.
  36. try a different ethernet cable
  37. I have tried 3 different ethernet cables already, in different rooms, plugged into different switches, got a surge protector with an ethernet guard, tried it directly to the modem, and it even does it when an ethernet cable is just plugged into a laptop running off battery and nothing else.. i'm fairly confident the ethernet cord is not the issue.
    It's particularly bad right now.. and I have no idea why..
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