[SOLVED] Brand new PC lost power after an hour

[philzilla]

Hi, thanks for letting me ask this question. So last night I helped a friend build his first PC. This was my second time building a PC.

All the parts were brand new. Everything was going fairly well. We had some trouble figuring out how to connect the GPU to the power supply but we finally figured that out. And then we had some difficulties with the front panel connections. The first time we plugged things in incorrectly and the PC wouldn't power on. We fixed that though and the PC booted up.

The PC was up running. I checked if it had the latest version of BIOS... it did. I installed Windows 10 pro from a USB drive. We booted the PC up and it finished the Windows install. After registering his license we started downloading programs and drivers, etc. The wifi was working... things were looking good.

At this point the PC has been on for about a hour and he's still downloading apps when suddenly the screen goes black and his computer powers off. We try to turn it back on and the fans spins for a half second and then nothing (not even fans). We try pressing the power button again and nothing. I plug the computer into a different outlet and nothing.

What should we do next? Did we get a faulty PSU? Is that where I should start?

Here's the part list: https://pcpartpicker.com/user/philzilla/saved/#view=7CykXL
CPU: AMD Ryzen 5 3600 3.6 GHz 6-Core Processor
Motherboard: MSI B450 TOMAHAWK MAX ATX AM4 Motherboard
Memory: G.Skill Ripjaws V 16 GB (2 x 8 GB) DDR4-3600 Memory
Storage: Western Digital Blue 1 TB M.2-2280 Solid State Drive
Video Card: Gigabyte GeForce RTX 2070 SUPER 8 GB GAMING OC 3X Video Card
Case: NZXT H510 ATX Mid Tower Case
Power Supply: EVGA SuperNOVA GA 750 W 80+ Gold Certified Fully Modular ATX Power Supply
Wireless Network Adapter: Asus PCE-AC55BT B1 PCIe x1 802.11a/b/g/n/ac Wi-Fi Adapter

Windows 10 Pro

 

[Ralston18]

My thought is that perhaps the computer warmed up, something expanded, and a short resulted.

Unplug, open the case, and carefully double check all card seatings, RAM seating, cable connections, jumpers, etc.. With a new build a connection or seating that feels tight may actual not be tight, and cause some disconnection due to expansion and any resulting movement.

Use a bright flashlight to inspect for any wires that are crimped, twisted, crushed, or have bare metal showing.

Ensure that all are fully, squarely (not tilted), and fully in place.

Check all screws and standoffs. Ensure that any disconnected/unused cables are not touching metal.

 

[philzilla]

My thought is that perhaps the computer warmed up, something expanded, and a short resulted.

Unplug, open the case, and carefully double check all card seatings, RAM seating, cable connections, jumpers, etc.. With a new build a connection or seating that feels tight may actual not be tight, and cause some disconnection due to expansion and any resulting movement.

Use a bright flashlight to inspect for any wires that are crimped, twisted, crushed, or have bare metal showing.

Ensure that all are fully, squarely (not tilted), and fully in place.

Check all screws and standoffs. Ensure that any disconnected/unused cables are not touching metal.

Thank you for your reply! If all the connections and seatings check out okay, what would you recommend doing next?

A short sounds scary. Does that mean a part could be potentially ruined? There was a second gen USB cable that the motherboard didn't support so we had to leave that loose. I'm hoping that wasn't resting on metal. I'll have to check that out tonight.

 

[Ralston18]

A short basically means that electrical current went somewhere it normally should not be going.

Electrical grounding/earthing (if properly done) provides protection by directing current along the easiest path and all the energy goes that way versus through (and possibly damaging) sensitive components.

First I would go back to the motherboard's User Guide/Manual and the corresponding documentation for all devices. Double check the installation connections and any associated configurations, Read the fine print and all the notes. Just to verify that all is connected as it should be.

However, if the computer did work even for just an hour then an installation error is less likely.

What I would do next is to reduce the computer to as minimal hardware configuration as possible.

Objective being to at least achieve a successful boot up. Failing that, then the next step is to start swapping in known working components. Or try your current components in another known working system. There is some risk in that because a failed component may cause a domino effect and take other devices out.

At some point it should become apparent that one particular component is the issue.

Do you have a multimeter and know how to use it? Or a knowledgeable Family member or friend who does?

You can test the PSU to some extent. Not a full test as the PSU is not under load. But an out-of-spec voltage may be very telling.

Reference:

https://www.lifewire.com/how-to-manually-test-a-power-supply-with-a-multimeter-2626158

Just work carefully and methodically as you troubleshoot. Keep notes. Include a process of elimination as you test.

 

[norcalsc]

disconnect all drives and wifi adapter and see if it will boot to bios

 

[philzilla]

UPDATE: It was a faulty PSU that was the problem. Just an unlucky fluke.

After checking all of the connections, everything seemed fine. So we went to Best Buy, bought a new power supply, swapped out the old one and it powered on instantly.

Thank you for all the advice and ideas!