A REAL MYSTERY: Computer periodically wouldn't POST, then bricked itself, and came back to life ONCE. Now its perma-bricked again.

[Raintech]

Components:

CPU - i5 11600k

Mobo - MSI z590-A Pro

RAM - 3200 mhtz Kingston Hyperx Fury 32gb kit (16gb x 2sticks) DDR4 (not the rgb version)

GPU - Gigabyte GTX1080 Windforce

PSU: Corsair RM750i, 750 watt gold

Bios version: 7D09v12 (latest version) and also tried 7D09v11 (2nd latest version) from MSI's website.

Storage: 4x SATA drives; Samsung 850 EVO SSD, Samsung 840 PRO SSD, Western Digital 1 TB HDD. Barracude 256gb HDD.

 

Current symptoms:

No post, can't get into bios. Fans on. LED lights on. Monitors show no signal detected black screen. DRAM ez-debug error light is ON; Motherboard owner's manual indicates this means "Memory not detected or fail". Can't get to windows login, can't open boot select menu, no keyboard shortcuts work. 

 

History of system:

System is currently about 2 months old. Worked flawless for the first month.

After 1 month: System would periodically fail to POST. This was VERY infequent, Happened MAYBE a total of 4-5 times and a single off+on always fixed the issue first try.

Very conservative overclock ran for first month, temps and voltage well within safe parameters (1.39 volts 90 degrees under small FFT Prime95, 4.6ghtz all cores boost to 4.9ghtz, RAM timings and voltage left at defaults)

Reset bios/overclock to defaults when infrequent failure to POST started happening a ~month ago.

 

Trouble started 2 days ago; Would not post. THEN COMPUTER WORKED JUST FINE for 8 hours. And now it's bricked again.

Starting 2 days ago, after no changes to hardware/software at all, the problem first started occuring PERSISTANTLY. Computer wouldn't post Tried turning off+on a dozen times. Never posted. Started troubleshooting. Will list troubleshoot steps below; but after everything was said and done, i got tired, decided to put everything back together for the folks at the computer store to take care of.

 

And as you would on a long wait on the phone, start powering on+off the system... after the 6th or so powercycle whilst on the phone after everything was reassembled the computer just started RIGHT BACK UP. It showed a cmos-cleared screen which is understandable since I did indeed clear the CMOS several times, pressed F2, into BIOS, set everything to defaults (noticed bios version was updated to a different version thanks to troubleshooting steps), booted up into windows and she was working perfectly fine for the next ~8 hours. 

 

Got sleepy, powered off the system, went to bed. its not the next morning and computer won't post or boot anymore. Same symptoms. It's been about 20 power cycles on and off.

 

 

Troubleshooting steps taken:

 

Tonnes of attempted reboots between each step ofc. Some reboots the power was left on for multiple minutes, up to a half hour incase bios was taking a while to load up and/or i was looking things up online.

• Keyboard shortcuts: Tried pressing DEL to enter bios, pressing F8 or F11 to enter boot select/safe boot. Tried ctrl+win+shift+B to reboot graphics driver. Nothing worked, screen remains black. 
• Cleared CMOS by shorting the 2 CMOS pins with a paperclip/screwdriver.
• Validated GPU and monitors and monitor cables; Tested GPU + Monitors in a known good working computer ; They all work fine.
• Plug monitors into onboard motherboard display output WITHOUT the gpu installed at all. Still no post.
• Tried booting PC with no peripherals or storage devices attached; Still no post.
• Tried booting PC with just a USB stick with a win10 boot drive loaded onto it; no post
• Tried multiple different keyboards ; nothing on screen, can't get to bios or boot menu.
• Cleared CMOS by removing CMOS battery completely - taking care to do the whole "remove the battery for 10 seconds and press power button to clear residual energy" nonsense. No luck
• Flashed BIOS using latest BIOS on MSI's website. Repeated the same for the 2nd latest BIOS version as well. 100% for sure know the bios flash worked because when the computer randomly unbricked itself the bios looked different that one time.
• Checked and reseated all power cables, both at the motherboard end, and the Type-4 modular PSU end. Disconnected and reseated 8 pin CPU cable, 24 pin motherboard cable, and GPU power cables. Note that my motherboard has a 4pin supplementary CPU power cable slot, but my PSU doesn't have a cable for it so its unplugged. Been unplugged for the past 2 months and has caused no issues.
• Reseated RAM sticks ensuring clicks, switched the 2 RAM stick positions, tried 2 RAM sticks in slots 1 and 3 instead of 2 and 4,
• Tried 1 RAM stick only; Just 1 stick installed into slot 2, tried the OTHER stick in RAM slot 2. Repeat the same for RAM slot 1
• Reseated CPU in socket using a flashlight to inspect for damage or debris; No damage or dust visible on either CPU or socket.
• Swapped out the PSU's power cable because why not?
• Tried different power socket on the wall because why not?

 

at this point it had been working on the PC for multiple hours and got pretty tired, so decided to give up and start the RMA process.

->Called Computer Store to start booking a service 

->Figured I'd have to bring the whole system in for the computer guys to have a look so put everything back together.

->Started turning the computer on+off multiple times because long wait time for the computer guys.

 

AND THEN SHE STARTED RIGHT UP

Computer was absolutely fine for the next 8 hours. All devices detected. All 32gb of ram detected. All storage devices detected. I backed up all my data, even got some work done, and at the end of the evening played some video games. Monitored my temps, and voltages. Everything seemed absolutely fine. CPU was boosting up to boost clocks and everything.

 

Got tired, figured I was in the all clear. Powered off the computer and went to bed.

 

It's now the next morning, and computer won't post anymore. It's back to doing it's overpriced-brick-impersonation.

 

I have a known good working configuration right now so I don't want to start pulling her apart again before I consult some folks. WHAT THE FLIP IS GOING ON??!? All I've done the past hour is tried clearing the CMOS again and making sure all my power/motherboard/psu cables are firmly seated and power cycling the computer like 20 times, and then type up this post.

 

Any ideas what could be going on? What could possibly cause a known good working system for ~2 months to suddenly stop posting?

 

[Dutch_Master]

You have warranty on parts and even assembly if you bought it pre-configured. Make sure all OC options are off, so you have a 'standard' system (it should, as you've done the CMOS clearing already). Don't bother any further, let the supply chain peeps worry about it.

[Raintech]

2 minutes ago, Dutch_Master said:

You have warranty on parts and even assembly if you bought it pre-configured. Make sure all OC options are off, so you have a 'standard' system (it should, as you've done the CMOS clearing already). Don't bother any further, let the supply chain peeps worry about it.

I bought the components and assembled it myself. I consider myself a fairly experienced system builder and haven't run into these issues before.

 

My computer store is known for having rather long customer service waiting times; They handle a very large amount of orders. On top of that, their closest brick and mortar store to me was recently closed indefinitely during the pandemic pending a relocation somewhere else; it's still closed as of today. The other nearest store to me is a good 30+ minute drive away.

 

I would definitely give it back to them for servicing but they often require us to drop off the computer for servicing, and tehn come back once they call us... perhaps up to days or even a week later.

[Raintech]

Update: Dropped off parts to computer store on Saturday. Sunday is a non business day so it took them until Monday to let me know they think it's a motherboard issue. Apparently my MSI z590-A Pro is defective, and fails to POST most of the time, and even the computer guys have no idea why. Physically there is 0 damage or visible defects on the board.

To no ones surprise they were out of stock on this particular board and needed time to order in a replacement. Just picked up my new motherboard, the computer guys have tested it and confirmed it seems fine. Hopefully this board doesn't need to be RMA'd either or I'm swearing off MSI products for the rest of my life.

Main takeaway; RMA'ing parts is super stressful and if something doesn't make sense, it's probably due to a defective component and should be taken back to where you purchased it even if its a pain in the ass.