MSI Mobo wont power - Page 1
Forum section: electronics / repair

author: myster1086
author_rank: Contributor
timestamp: November 12, 2018, 12:09:35 am
content: got a msi motherboard, wont power on. weird little issue. tried no ram no extras powers on. when i unplug the 4 pin cpu it will power everything with it nothing, its not a short nor dead cpu. power supply is 500w so i know its not that. could it be a incompatible cpu?

author: cdev
author_rank: Super Contributor
timestamp: November 12, 2018, 01:31:17 am
content: What does the MSI web site say its compatible CPUs are? Is the four pinned one (probably a typo?) you've put in it on that list?Quote

author: Nusa
author_rank: Super Contributor
timestamp: November 12, 2018, 01:38:42 am
content: "power supply is 500w so i know its not that"No you don't, not unless it's a known good supply from another working system that uses that 4-pin connector.But you've identified a symptom. By 4-pin cpu, I assume you mean the 4-pin power connector near the CPU.When you say "nothing", does that mean the power supply doesn't turn on?How do you know it's not a short? That's actually the most likely reason the 4-pin connector would be doing this.Possibilities that jump to mind:4-pin connector is mis-wired. (find correct wiring on the internet, confirm visually by wire colors)Mating 4-pin connector on MB is installed incorrectly. (find closeup of MB on internet and confirm)If you're putting a 4-pin into an 8-pin socket, you managed to put it in wrong, despite the pin keying.Motherboard is defective in some other way.

author: Specmaster
author_rank: Super Contributor
timestamp: November 12, 2018, 03:37:54 pm
content: Quote from: Nusa on November 12, 2018, 01:38:42 amA MB still requires the other multipin header plugged in as well as the 4 pin one next to the CPU.You don't say if this is a new build your doing, or if it was working and suddenly stopped. To offer some more meaningful help requires more information coming from you to set the scene for us in order that can an idea of the problem that is correct.

author: myster1086
author_rank: Contributor
timestamp: November 14, 2018, 12:53:21 pm
content: Alrighty off of memory from reading comments.Yes 4 pin power next to CPU.Mobo powered on previously, installed windows, set up, powered down moved to other room.Power supply is working, as its my main one for my computer running right now.Nothing means, when I don't power the 4 pin to CPU fans, HDD and lights all come on and strangley act normal. I try with the 4 pin added I get nothingIts not a short that I can tell, no blown anything, no damage, nothing.CPU is compatible, its not been replaced and worked just fine.Another thing I've noticed, PCI cards also cause it not to want to power on.

author: Specmaster
author_rank: Super Contributor
timestamp: November 14, 2018, 06:03:09 pm
content: On the MSI MB, have you got both the 4 pin power plug plugged in plus the 20 pin plug, plugged in its respective socket over wise it will not power up at all.The 4 pin plug supplies 12v for the CPU and the 20 pin plug also supplies 3.3v, 5v and 12v for other parts but it is essential to have both plugged in and the way that seem to be describing it is you only using the 4 pin plug supply???This site here might help you to learn a bit more about ithttp://www.informit.com/articles/article.aspx?p=30273&seqNum=4

author: Richard_L
author_rank: Contributor
timestamp: November 15, 2018, 12:26:01 am
content: A little fleshing out of the details and chronology is required... is this correct?You've acquired a second-hand, unknown model of MSI motherboard in an unknown condition?You've also acquired second-hand in unknown condition, or had your own known-good spare RAM, CPU and an HDD/SSD which you've added to it?You've powered it up successfully in "Room A" using your own known-good PSU from your own PC?You've had it working long enough in "Room A" to install Windows on it?You've moved it to "Room B" and it has never worked properly again?When it "Room B" it only "comes to life" (fans, lights etc) when the additional 4-pin 12V CPU power connector is disconnected from the motherboard but won't get past POST or boot?Inserting a PCI card then stops the motherboard from displaying even the faint signs of life described in the line above?Questions:Apart from the MSI motherboard, what other components in the faulty machine are new/used, yours/someone-else's, condition unknown/known-good?What else changedwhen you moved it from Room A to Room B?Did the motherboard get put into or taken out of a case when you moved it into Room B?Is it using a different PSU now it's in Room B to the one it was using in Room A?Do you mean it also "dies" when a PCI card is inserted or when aPCIecard is inserted?And if it is a PCIe card, is it a graphics card with a 6/8-pin PCIe 12V power connector of its own?What other 12V loads are connected? CPU heatsink fans? case fans? watercooling pumps?Speculations:The PSU really doesn't like it whenever any 12V load (either CPU or expansion card) is connected to this motherboard for whatever reason and over-current protection is immediately turning off the 12V rail on your PSU.If you installed the motherboard into a case it had never been in before when you moved it into Room B, check the positions of the stand-offs and whether they're all needed.I can't offer any more advice without knowing more details about the problem!

author: myster1086
author_rank: Contributor
timestamp: November 18, 2018, 01:18:49 am
content: Quote from: Richard_L on November 15, 2018, 12:26:01 am

author: cdev
author_rank: Super Contributor
timestamp: November 26, 2018, 01:34:28 am
content: For a few dollars you can buy a PCI or PCIe diagnostic card that will display numbers that represent where a computer is in the boot process so you will see where it froze up.

author: myster1086
author_rank: Contributor
timestamp: November 28, 2018, 10:55:48 am
content: Would you have a link to one of these?