[SOLVED] PC doesn't POST anymore - either post loops or stops at random LED

[Defil1998]

Hey everyone!

I posted this on Reddit, too, but I figured I'd share it here too to increase my chance of getting to the bottom of this problem! Sorry, but this is going to be a long post! My rig:

• CPU: AMD Ryzen 3700x (stock cooler, Amazon warehouse)
• MOBO: Asus B550 Tuf Gaming (now Asus X570-F Strix)
• GPU: Gigabyte RTX 2080 windforce (used, 2 years old)
• PSU: Corsair TX650M (Amazon warehouse)
• RAM: Crucial Ballistix 2x16 GB 3600MHz RGB
• SSD: NVMe M.2 Sabrent Rocket 500 GB (PCIe 3.0)
• HDD: Maxtor 2 TB portable hard drive (opened and connected as internal)
• CASE: Corsair 275R

This was built on October last year, although I got the 2080 on January 2021, but it has been working fine ever since.

Here's the issue: my PC randomly rebooted (as if I pressed the physical reboot button) while I wasn't around, I just turned it on and I had a single chrome tab opened. The PC didn't POST, it got stuck with the DRAM LED on. This happened once already, all it took was turning off and on the PSU but this time it didn't work. Not only that, sometimes after rebooting the PC it gets stuck on either DRAM, CPU or VGA, although only rarely on CPU.

So, I tried the usual troubleshooting with the old motherboard:

• Resetting CMOS
• Reseating CMOS battery
• Flashing BIOS update through EzFlash Utility
• Reseating CPU
• Changing GPU (I had an old R7770 by XFX laying around)
• Unplugging HDD
• Reseating RAM

On this matter, when I tried one stick on B2 slot (which should have priority among the four) the PC started boot looping, i.e. getting all the way to VGA LED and immediately going back to DRAM as if I pressed the physical reboot button, then repeating indefinitely. Any stick on B2 slot had this effect, while any stick on A2 (the other priority slot) just made the PC stuck on any POST step as described before.

I thought that this could have been a motherboard traces issue, so I bought a new board (X570-F Strix) and rebuilt my PC, only to encounter the same issue. The thing is, this time it's A2 that is causing the boot loop, and not only that, this time I tried a single stick of RAM in any slot and it looks like A1 is doing the same as A2 while B1 and B2 are "fine" (still no POST, but it's better than boot looping I guess). I can't figure out the schematics, but as far as I know RAM slots are connected 2 by 2 to the CPU, so could this mean that I have a faulty CPU? I just hope that whatever started the issue didn't propagate it to the other components, or this will be impossible to solve. I'll try a different stick of RAM that I'll be borrowing from a friend of mine just to make sure it's not that, I'll keep you posted.

Thank you in advance!

 

[Lutfij]

GPU: Gigabyte RTX 2080 windforce (used, 2 years old)
+
although I got the 2080 on January 2021,
Since this was purchased used form another individual, was it purchased after it had been used for mining?

With the system disconnected from the wall and display, press and hold down the power button and then remove the GPU and the CMOS battery. Replace the battery after 30 minutes and inspect the GPU for any signs of a blown component or if you can smell anything being burnt on the PCB. I'd also ask you to source a replacement PSU that's built akin to the Corsair unit with the same if not 750W if not 650W of power for the entire system. Can you check and see what BIOS version you're working with for both (motherboards)platforms?

 

[Defil1998]

GPU: Gigabyte RTX 2080 windforce (used, 2 years old)
+
although I got the 2080 on January 2021,
Since this was purchased used form another individual, was it purchased after it had been used for mining?

I'm pretty sure it wasn't, although I can't be sure as I bought it through a Craigslist-like local website. The GPU didn't look in bad shape and benchmarks were consistent with what the card should have scored.

With the system disconnected from the wall and display, press and hold down the power button and then remove the GPU and the CMOS battery. Replace the battery after 30 minutes and inspect the GPU for any signs of a blown component or if you can smell anything being burnt on the PCB.

Unfortunately I already tried to reseat the CMOS battery, although it was for only 10 minutes and not 30. Should I do it again for a longer period? Also, I tried an old GPU I had laying around (that I was sure it worked before), no luck with that too. Either way, the 2080 looked fine, PCIe connector, PCB and all.

I'd also ask you to source a replacement PSU that's built akin to the Corsair unit with the same if not 750W if not 650W of power for the entire system.

While it would be cheaper than a new CPU for sure, do you reckon it's more probable that I have a faulty PSU rather than the CPU? I'm asking this because I'm waiting for a friend's 3700x to try on my system, but finding a new PSU would be a bit more difficult as they have lower wattage ones, so I would have to buy a new one to try it out.

Can you check and see what BIOS version you're working with for both (motherboards)platforms?

Unfortunately I didn't have the chance to boot on the new motherboard so I don't know which BIOS version it has, although I could always flesh the newest one through USB. On the "old" B550 I had a version released in August (2407 I think), although while troubleshooting I successfully updated to version 2423 (the latest available). I'm saying successfully because everything went right as Asus said it should.

Thank you for your help, by the way!

 

[rickypicky5]

While it would be cheaper than a new CPU for sure, do you reckon it's more probable that I have a faulty PSU rather than the CPU? I'm asking this because I'm waiting for a friend's 3700x to try on my system, but finding a new PSU would be a bit more difficult as they have lower wattage ones, so I would have to buy a new one to try it out.

Yes. CPUs rarely fail. PSUs, on the other hand, are far more likely to fail. Correct me if I'm wrong, but "Amazon Warehouse" indicates the PSU was used. Never a good idea to purchase a used PSU.

 

[Defil1998]

Yes. CPUs rarely fail. PSUs, on the other hand, are far more likely to fail. Correct me if I'm wrong, but "Amazon Warehouse" indicates the PSU was used. Never a good idea to purchase a used PSU.

It was used for sure, although it didn't look in bad shape, it just missed some cables which I luckily didn't need. The thing that made me think about CPU is the fact that two RAM slots are making the system boot loop, while the other two are just not posting, so I thought there was an issue in the shared channel on the Mobo or the CPU... Although, now that I think about it, a faulty PSU could explain why the system stops at different steps each time, it could just be that that component isn't getting a good amount of power in that moment.

Also I just remembered that two or three times I got a black screen for a couple of seconds while doing random things (either web browsing, gaming, watching videos) but I wasn't able to figure out what was happening, there were no particular windows events registered. Instable power to the gpu?

 

[rickypicky5]

It was used for sure, although it didn't look in bad shape, it just missed some cables which I luckily didn't need. The thing that made me think about CPU is the fact that two RAM slots are making the system boot loop, while the other two are just not posting, so I thought there was an issue in the shared channel on the Mobo or the CPU... Although, now that I think about it, a faulty PSU could explain why the system stops at different steps each time, it could just be that that component isn't getting a good amount of power in that moment.

Also I just remembered that two or three times I got a black screen for a couple of seconds while doing random things (either web browsing, gaming, watching videos) but I wasn't able to figure out what was happening, there were no particular windows events registered. Instable power to the gpu?

A faulty PSU can cause all sort of issues.

Is it under warranty - probably not an amazon warranty, but maybe still under the Corsair warranty? That unit, when purchased new, has a 7 year warranty.

 

[Defil1998]

A faulty PSU can cause all sort of issues.

Is it under warranty - probably not an amazon warranty, but maybe still under the Corsair warranty? That unit, when purchased new, has a 7 year warranty.

I'm pretty sure I can't use Corsair's warranty as I wasn't the original buyer, but Amazon Warehouse could have something for me, I'll check. Couldn't I check the PSU by itself with a voltmeter before sending the PSU back?

 

[rickypicky5]

I'm pretty sure I can't use Corsair's warranty as I wasn't the original buyer, but Amazon Warehouse could have something for me, I'll check. Couldn't I check the PSU by itself with a voltmeter before sending the PSU back?

I'm not exactly sure how to check the PSU with a voltmeter, or even if that is a good way to check one. Maybe someone else here can advise? Ideally, you could borrow a friend's know working PSU (of sufficient wattage) and test with it?

 

[Defil1998]

I'm not exactly sure how to check the PSU with a voltmeter, or even if that is a good way to check one. Maybe someone else here can advise? Ideally, you could borrow a friend's know working PSU (of sufficient wattage) and test with it?

Unfortunately the "sufficient wattage" part makes that difficult... I think I'll just check with a friend's CPU if the system boots, same with the RAM, then if the system still doesn't work I'll buy a new PSU. Apart from that, I think I'll be getting a new one for Christmas nonetheless, you're right about used PSUs!

Thank you for your help, though, I really appreciated it!

 

[rickypicky5]

Good luck and let us know

 

[Defil1998]

So, I managed to meet up with a friend and try his components. We tried his RAM and/or his PSU, but still nothing to do, the same issue happened. We even tried disconnecting everything, I mean both internal and external USB connectors, but it didn't change anything. Now that I've tried another GPU, Mobo, RAM and PSU I'd say that the culprit is the CPU, I can't think of anything else. I'll order a new one today, it should arrive by tomorrow so I'll keep you posted.

Thanks everyone for your help!

 

[rickypicky5]

I didn't notice before now that your CPU is also "Amazon Warehouse". Good luck with the new one!

 

[Defil1998]

I didn't notice before now that your CPU is also "Amazon Warehouse". Good luck with the new one!

Thank you! Don't worry, this time I got a new one hahaha I even spent 30 euros more to get the one sold my Amazon instead of a third party seller!

 

[helper800]

So, I managed to meet up with a friend and try his components. We tried his RAM and/or his PSU, but still nothing to do, the same issue happened. We even tried disconnecting everything, I mean both internal and external USB connectors, but it didn't change anything. Now that I've tried another GPU, Mobo, RAM and PSU I'd say that the culprit is the CPU, I can't think of anything else. I'll order a new one today, it should arrive by tomorrow so I'll keep you posted.

Thanks everyone for your help!

As far as I am aware, most manufacturers will honor their warranty even without a receipt from when it was new by giving you the warranty duration from its date of production. For instance, lets say your PSU was manufactured today the warranty, even second hand, would last until 10/4/2028. If you are worried about whether or not they will honor their warranty because it is a second hand device, you will figure that out when you try to RMA it. Either they won't care, or they will ask you directly. How you answer that question is up to you.

 

[Defil1998]

As far as I am aware, most manufacturers will honor their warranty even without a receipt from when it was new by giving you the warranty duration from its date of production. For instance, lets say your PSU was manufactured today the warranty, even second hand, would last until 10/4/2028. If you are worried about whether it not they honor their warranty because it is a second hand device, you will figure that out when you try to RMA it. Either they won't care, or they will ask you directly. How you answer that question is up to you.

Thank you for the insight, this will come in handy one day for sure. Now that I think about it, I'll try to RMA the CPU while I'm waiting for the new one!

 

[Defil1998]

Hey everyone,
I wanted to update you on my issue. It turns out my 3700x was somewhat dead, I bought a 5900x and everything works fine now! So unfortunately I had to upgrade, but everything went well!

So thanks again for the help!

 

[helper800]

Hey everyone,
I wanted to update you on my issue. It turns out my 3700x was somewhat dead, I bought a 5900x and everything works fine now! So unfortunately I had to upgrade, but everything went well!

So thanks again for the help!

I am glad that we were able to figure it out with you. Cheers, how you can now enjoy your PC again!