PC hangs so hard power button isn't working

[AyoKeito]

Hey everyone.
I'm using my PC to game and encode H.264 and H.265 videos. I've been doing that since August and it was fine.
Yesterday, i've left my PC encoding again and came back to see that it's completely frozen. It hang up so hard, that power button wasn't working at all (i don't have a reset on my case but i'm pretty sure i wouldn't have any luck with it as well). Power button on the mobo itself isn't working too. I had to unplug my PSU to shut down my PC. To make things worse, it didn't boot up after that. No mobo debug LEDs were lighting up: only RGB (thank god!), HDD and fans working. I've unplugged my PC to disassemble it later but tried to turn it on 20 minutes later - it worked!.. For some time.
Here's how crash happens: first, mouse cursor changes it's state to "loading something" (i think you know what i mean), a second later screen freezes, USB devices disconnect (RGB goes off) and that's pretty much it. No weird sounds, and screen stays on, like i just made a screenshot, lol. That also allows me to see that my CPU isn't overheating, crashes happen even with 70-85C CPU temperature. There are no events in Windows event viewer regarding that crash, and no BSOD dumps.
---longread now---
Here's what i got: I'm pretty sure that this crash is hardware related, probably CPU temperature or something like that, because it's a 100% crash on the first 10 minutes of H.265 encoding (AVX2, runs CPU very hot, 80-90C). H.264 was crashing too, until i've set up a manual Ryzen Master profile 4000 all-core with 1.23V. 4100@1.25V was a no-go. H.265 is unstable even at 3800@1.2V. Games are mostly fine, i've had just one crash in a few hours of playing R6 Siege with PBO before i've switched to manual profile, i'll test more with it later. So reducing CPU temperature increases stability.
RAM is probably OK. I've been running 3666CL16@1.38V for a month and it was okay. I've had one annoying memory error that showed up after hours of testing with Ryzen DRAM Calculator test, and Prime95 large is fine after 30 minutes of testing (will run a longer test later). I also have some low speed RAM in my other PC so i will try that later too. I've tried running my RAM at 3200 (coupled with IMC 1:1) full auto, that didn't help. On a side note, when my PC hangs up, DRAM debug LED lights up. But i still think it's not RAM, but CPU IMC or something related to mobo. When my PC wasn't booting (see below for a "fix"), debug LEDs didn't show anything even with no RAM installed (i guess that means that boot failed even before RAM test started).
BIOS settings were probably fine. I've manually adjusted a bunch of them to what i think is safe, including all voltages on Auto and all AMD CBS settings on Auto too. That didn't help. I'm now in a process of testing with Optimized Defaults.
PSU is probably fine, but i haven't tested it at all yet. I have other PSU to test, tho.
OS has to be fine since i believe no OS failure can prevent PC from booting and\or reacting to power button.

Other problems i've had before this occurred:
One of my old SATA SSD's disappeared from system a few months ago. It was appearing and disappearing with reboots for a few days but now it's completely gone from OS and BIOS for more than a month. Since it was just a 120GB cheapo cache SSD, i've decided to just ignore that for now.
RAM OC was broken with the last BIOS update for my mobo (nothing above 3200 boots, even on full auto). RAM OC was fine before it, but now i have to OC through Ryzen Master (this one still OC's RAM fine). Also, that one update made my previously 1000% stable profile throw one single error in RAM test. But that update was installed in the end of November, and crashes appeared yesterday.

I believe my motherboard or CPU has gone bad.

Also, there's how i fixed my PC not booting after that crash: i've decided to take it apart again and started unplugging things. After i've removed pretty much everything but 1 RAM stick, CPU and 2 M.2 drives, i've decided to turn my PC on to see if it boots. It did! So i've returned my waterblock to it's place to try again - it didn't boot! I've reseated the waterblock again and applied less pressure now, only 1\2 of how long the screws go - now it boots fine. I've checked both CPU legs and socket and they both look OK. Since then, if my PC crashes, i "only" have to switch PSU off and on again. No longer waiting for nothing and clearing CMOS with a jumper to no avail. I'm going to test the BOX cooler if i manage to find the original backplate for my motherboard.
I'm going to take my mobo and CPU to a local shop next week to check which one of them failed, if any, but i'd appreciate your guesses on what's wrong with my system. I got my mobo from a local shop and i'll be ok with replacing it, since i'm not very happy with it anyway; but my CPU is whole other story, since i've bought it from another country. I will change it to 3950X if it's failed but on the other hand i hope it's not CPU because international shipping is not fun.

I'll run pretty much all the test you can suggest and i'll continue swapping parts to be sure it's either CPU or mobo later this day.

Specs:
AMD Ryzen 3900X
ASUS Prime X570 Pro
4x8GB DDR4 Patriot Viper Steel 3733CL17 running at 3666CL16@1.38V
A bunch of HDDs and SSDs, system is running from Samsung 970
Cooler Master Power Supply V750 750W
ASUS 1080TI FE
Windows 10 x64
Custom water loop, no leaks (that would be obvious)

 

[enxo218]

ok ssd problem, did you try switching ports or sata cable and if problem persists did you try connecting it externally and checking behaviour then test drive for errors

next the main problem, the fact that pc is non responsive to button press shutdown and must be unplugged I think it's either psu or mobo , you should try psu first see what happens

 

[AyoKeito]

ok ssd problem, did you try switching ports or sata cable and if problem persists did you try connecting it externally and checking behaviour then test drive for errors

next the main problem, the fact that pc is non responsive to button press shutdown and must be unplugged I think it's either psu or mobo , you should try psu first see what happens

I've not tested SSD externally... Yet. I will do that in the next few hours when i get home. I'll try external USB adapter to do that.
I presonally think that it's either CPU or mobo, but PSU is not out of equation yet. I have a decent PSU to replace and check, so i will do that too.

 

[enxo218]

well something may be happening to cause the hang up while turned on and may be a different problem on its own but the cpu is not involved in hard button press shutdown process its literally a physical switch at this point and the main actors are the button the psu and mobo connectors no command execution is expected from cpu

 

[AyoKeito]

well something may be happening to cause the hang up while turned on and may be a different problem on its own but the cpu is not involved in hard button press shutdown process its literally a physical switch at this point and the main actors are the button the psu and mobo connectors no command execution is expected from cpu

That's useful. I thought that nothing in the PC actually happens without the CPU. Will shift my attention from CPU to PSU then.

 

[Bill_Bright]

its literally a physical switch at this point and the main actors are the button the psu

Sorry but that is not true at all. Yes, it is a physical switch, but, as always, all that switch does is short two pins on the motherboard. That short signals the BIOS firmware to initiate the shutdown (or startup) process. This switch does NOT have a direct connection to the PSU.

@AyoKeito - do note with many motherboards, you have to press and hold the case's front panel power button for 4 - 5 seconds to force a shutdown. If you simply press and release, that typically does nothing, or starts a restart - depending on the setting in the BIOS Setup Menu, and assuming everything is working properly. Your motherboard's integrated power button effectively just shorts those two pins too. On ATX PSUs, the only switch that directly affects the PSU is the master power switch on the back of the PSU (if yours has one).

You need to swap in that extra PSU before assuming it is anything else since EVERYTHING inside the computer case depends on good, clean, stable power.

 

[TheoneandonlyMrK]

Hey everyone.
I'm using my PC to game and encode H.264 and H.265 videos. I've been doing that since August and it was fine.
Yesterday, i've left my PC encoding again and came back to see that it's completely frozen. It hang up so hard, that power button wasn't working at all (i don't have a reset on my case but i'm pretty sure i wouldn't have any luck with it as well). Power button on the mobo itself isn't working too. I had to unplug my PSU to shut down my PC. To make things worse, it didn't boot up after that. No mobo debug LEDs were lighting up: only RGB (thank god!), HDD and fans working. I've unplugged my PC to disassemble it later but tried to turn it on 20 minutes later - it worked!.. For some time.
Here's how crash happens: first, mouse cursor changes it's state to "loading something" (i think you know what i mean), a second later screen freezes, USB devices disconnect (RGB goes off) and that's pretty much it. No weird sounds, and screen stays on, like i just made a screenshot, lol. That also allows me to see that my CPU isn't overheating, crashes happen even with 70-85C CPU temperature. There are no events in Windows event viewer regarding that crash, and no BSOD dumps.
---longread now---
Here's what i got: I'm pretty sure that this crash is hardware related, probably CPU temperature or something like that, because it's a 100% crash on the first 10 minutes of H.265 encoding (AVX2, runs CPU very hot, 80-90C). H.264 was crashing too, until i've set up a manual Ryzen Master profile 4000 all-core with 1.23V. 4100@1.25V was a no-go. H.265 is unstable even at 3800@1.2V. Games are mostly fine, i've had just one crash in a few hours of playing R6 Siege with PBO before i've switched to manual profile, i'll test more with it later. So reducing CPU temperature increases stability.
RAM is probably OK. I've been running 3666CL16@1.38V for a month and it was okay. I've had one annoying memory error that showed up after hours of testing with Ryzen DRAM Calculator test, and Prime95 large is fine after 30 minutes of testing (will run a longer test later). I also have some low speed RAM in my other PC so i will try that later too. I've tried running my RAM at 3200 (coupled with IMC 1:1) full auto, that didn't help. On a side note, when my PC hangs up, DRAM debug LED lights up. But i still think it's not RAM, but CPU IMC or something related to mobo. When my PC wasn't booting (see below for a "fix"), debug LEDs didn't show anything even with no RAM installed (i guess that means that boot failed even before RAM test started).
BIOS settings were probably fine. I've manually adjusted a bunch of them to what i think is safe, including all voltages on Auto and all AMD CBS settings on Auto too. That didn't help. I'm now in a process of testing with Optimized Defaults.
PSU is probably fine, but i haven't tested it at all yet. I have other PSU to test, tho.
OS has to be fine since i believe no OS failure can prevent PC from booting and\or reacting to power button.

Other problems i've had before this occurred:
One of my old SATA SSD's disappeared from system a few months ago. It was appearing and disappearing with reboots for a few days but now it's completely gone from OS and BIOS for more than a month. Since it was just a 120GB cheapo cache SSD, i've decided to just ignore that for now.
RAM OC was broken with the last BIOS update for my mobo (nothing above 3200 boots, even on full auto). RAM OC was fine before it, but now i have to OC through Ryzen Master (this one still OC's RAM fine). Also, that one update made my previously 1000% stable profile throw one single error in RAM test. But that update was installed in the end of November, and crashes appeared yesterday.

I believe my motherboard or CPU has gone bad.

Also, there's how i fixed my PC not booting after that crash: i've decided to take it apart again and started unplugging things. After i've removed pretty much everything but 1 RAM stick, CPU and 2 M.2 drives, i've decided to turn my PC on to see if it boots. It did! So i've returned my waterblock to it's place to try again - it didn't boot! I've reseated the waterblock again and applied less pressure now, only 1\2 of how long the screws go - now it boots fine. I've checked both CPU legs and socket and they both look OK. Since then, if my PC crashes, i "only" have to switch PSU off and on again. No longer waiting for nothing and clearing CMOS with a jumper to no avail. I'm going to test the BOX cooler if i manage to find the original backplate for my motherboard.
I'm going to take my mobo and CPU to a local shop next week to check which one of them failed, if any, but i'd appreciate your guesses on what's wrong with my system. I got my mobo from a local shop and i'll be ok with replacing it, since i'm not very happy with it anyway; but my CPU is whole other story, since i've bought it from another country. I will change it to 3950X if it's failed but on the other hand i hope it's not CPU because international shipping is not fun.

I'll run pretty much all the test you can suggest and i'll continue swapping parts to be sure it's either CPU or mobo later this day.

Specs:
AMD Ryzen 3900X
ASUS Prime X570 Pro
4x8GB DDR4 Patriot Viper Steel 3733CL17 running at 3666CL16@1.38V
A bunch of HDDs and SSDs, system is running from Samsung 970
Cooler Master Power Supply V750 750W
ASUS 1080TI FE
Windows 10 x64
Custom water loop, no leaks (that would be obvious)

I have had similar experiences crunching 24/7.

Setting my memory to looser timings stopped it happening.

Your issue might not be this but this is very very easy to check.

Plus with four memory sticks you are pushing the integrated memory controller hard and Possibly (im not 100%. Sure) beyond it's rated spec with all memory channels in use.

With mine it was technically the slow but continued heating of the memory eventually made it unstable, crazey fan speeds also cured it but wasn't a satisfactory fix.

 

[Bill_Bright]

The thing here is the system worked fine since August, then started having problems. Issues with timings and fully populating RAM slots typically start appearing right away, or at least after some other significant change. That's why I suspect a failing PSU here first. At least I recommend eliminating it from the equation first by swapping in a known good one.

 

[AyoKeito]

do note with many motherboards, you have to press and hold the case's front panel power button for 4 - 5 seconds to force a shutdown

Yep, it's not the first time i've tried shutting down my PC with that button since i don't have a reset button on my case, i've been holding it long enough. Not only that, but i've tried the button on the motherboard: it didn't do anything as well.

I have had similar experiences crunching 24/7.
Setting my memory to looser timings stopped it happening.
Your issue might not be this but this is very very easy to check.

The thing here is the system worked fine since August, then started having problems. Issues with timings and fully populating RAM slots typically start appearing right away, or at least after some other significant change. That's why I suspect a failing PSU here first. At least I recommend eliminating it from the equation first by swapping in a known good one.

Yep, that RAM kit was tested a lot of times and most of times it came out clean. I've been running memory tests for nights when i was doing RAM OC. I will still swap it out for a cheap set from the other PC, but at this point i'm pretty sure RAM is fine since i just failed the "Optimized Defaults" test that make RAM run at 2400 or so... It actually failed almost instantly but i wasn't there to see that.

I just came back and here are some more details:
As i've said earlier, setting "Optimized Defaults" in BIOS doesn't help.
I've also removed dead SSD from the PC and attached it via external USB: it's certainly dead, not detected in CrystalDiskInfo and detected as a "USB Device" in Device Manager. It's also showing up in Disk Management, but it's telling me i have to initialise the disk which instantly throws an error saying "Device is not ready". On a side note, BIOS is reporting normal voltages (i know i can't really trust software monitors): +12V is at 12.076V, +5V is at 4.949V and +3.3V is at 3.280V

Now, i don't have time to do the PSU swap right now, but i'm going to run another RAM test overnight: i want to use both memtest86 and prime95. Which should i leave running for longer? I suspect that Prime95 will eventually "overheat" my CPU into the crash even in large FTT mode, so i think i'll leave it running for 4-5 hours and leave memtest86 running for another ~13 hours.
For tomorrow, i'm going to swap RAM and PSU and see how it goes.

 

[Bill_Bright]

Yep, it's not the first time i've tried shutting down my PC with that button since i don't have a reset button on my case, i've been holding it long enough. Not only that, but i've tried the button on the motherboard: it didn't do anything as well.

All the more reason to swap in a known good PSU so you know you are feeding everything else good, clean power. Until you verify power everything is a guess.

Prime95 would be wasting your time. And frankly so is MemTest86 at this point. For one, while MemTest86 (make sure it is that one - there are several with similar names that are not as good, or current), is good, no software based memory tester is conclusive. If they report errors, the RAM is bad, but they frequently report no errors yet the RAM still fails in real-world use, or when paired with other RAM.

To conclusively test your RAM, you need to use sophisticated and very expensive test equipment, like this $2,495 Memory Tester - and that's for the cheap model! So it is usually easier (and cheaper!) to swap in known good RAM and see what happens.

And besides, I have never seen, nor do I see how faulty RAM will prevent the power button from working. IMO, until you verify power, you are just spinning your wheels.

Again, forget Prime95 - even if it fails, it will not point you to the problem. If you are set on running MemTest86, it needs to run for several complete passes - I usually run it overnight and you should get "zero" errors. Even just one error indicates a bad stick(s).

 

[TheoneandonlyMrK]

Yep, it's not the first time i've tried shutting down my PC with that button since i don't have a reset button on my case, i've been holding it long enough. Not only that, but i've tried the button on the motherboard: it didn't do anything as well.



Yep, that RAM kit was tested a lot of times and most of times it came out clean. I've been running memory tests for nights when i was doing RAM OC. I will still swap it out for a cheap set from the other PC, but at this point i'm pretty sure RAM is fine since i just failed the "Optimized Defaults" test that make RAM run at 2400 or so... It actually failed almost instantly but i wasn't there to see that.

I just came back and here are some more details:
As i've said earlier, setting "Optimized Defaults" in BIOS doesn't help.
I've also removed dead SSD from the PC and attached it via external USB: it's certainly dead, not detected in CrystalDiskInfo and detected as a "USB Device" in Device Manager. It's also showing up in Disk Management, but it's telling me i have to initialise the disk which instantly throws an error saying "Device is not ready". On a side note, BIOS is reporting normal voltages (i know i can't really trust software monitors): +12V is at 12.076V, +5V is at 4.949V and +3.3V is at 3.280V

Now, i don't have time to do the PSU swap right now, but i'm going to run another RAM test overnight: i want to use both memtest86 and prime95. Which should i leave running for longer? I suspect that Prime95 will eventually "overheat" my CPU into the crash even in large FTT mode, so i think i'll leave it running for 4-5 hours and leave memtest86 running for another ~13 hours.
For tomorrow, i'm going to swap RAM and PSU and see how it goes.

Ryzen auto sets secondary and tertiary timings on start up , during boot, if they're not already set and on a mem boot fail , the memory you put in may not be 100% compatible so the system will do it's best but might not be settling on stable settings.
A ram crash can lock a ryzen up as you have had ,mine has, but as others are saying it could still be other things like the psu, and the ssd might have got corrupted during the crash or be the cause ,some ssds can be reinitialised and reformatted to bring them back to healthy ,others can't so good luck.

As others state there is some testing and swapping to do.

I always mention memory first in such because pulling all but one stick and setting jedec 2133 is usually a good isolator of it being a memory issue and it's quick and easy to do.

 

[Bill_Bright]

but as others are saying it could still be other things like the psu

"Could" being the operative word there. But since the RAM, motherboard, CPU, drives, graphics, you name it, "could" all fail if improperly powered, when troubleshooting electronics hardware, you start at the wall. Is it plugged in? Is it turned on? Are you feeding it correct and stable voltages?

 

[TheoneandonlyMrK]

"Could" being the operative word there. But since the RAM, motherboard, CPU, drives, graphics, you name it, "could" all fail if improperly powered, when troubleshooting electronics hardware, you start at the wall. Is it plugged in? Is it turned on? Are you feeding it correct and stable voltages?

Your attacking it from your perspective, which is right for you, your right just you and me have a meter to check such things, Even a spare Psu im just passing on easy options to check rather easy options as ever based on experience.

 

[TheLostSwede]

No need to panic about the power button, it happens. Flick the switch on the PSU, leave the system for a bit and it tends to power right back up. It's some weird ghost in the machine that crops up at times when things aren't stable. Worst case, unplug the ATX 24-pin power cable, leave it for a bit and it tends to boot up just fine. It's freaky when it happens, but it tends to be no big deal. The reset button wouldn't do anything when the system is in this state either.
I've had this happen a fair bit when trying to optimize my memory timings and as much as it's annoying, it doesn't do any damage to the system.

And maybe don't overlock the CPU manually? Most Ryzen 3000-series chips don't seem to be all that happy being manually overclocked.

Oh and are you on the latest UEFI? This makes a huge difference with your hardware.

Plus with four memory sticks you are pushing the integrated memory controller hard and Possibly (im not 100%. Sure) beyond it's rated spec with all memory channels in use.

I have four sticks at 3800MHz, not had a single problem with it, but admittedly, I haven't run the system at full tilt hours on end. To be fair, it seems the memory subsystem is really solid this time around, as once all the UEFI/AGESA bugs were ironed out, I haven't had a single glitch with my system. In fact, I'm surprised it works as well as it does, compared to my previous Ryzen 7 1700 rig.

 

[TheoneandonlyMrK]

No need to panic about the power button, it happens. Flick the switch on the PSU, leave the system for a bit and it tends to power right back up. It's some weird ghost in the machine that crops up at times when things aren't stable. Worst case, unplug the ATX 24-pin power cable, leave it for a bit and it tends to boot up just fine. It's freaky when it happens, but it tends to be no big deal. The reset button wouldn't do anything when the system is in this state either.
I've had this happen a fair bit when trying to optimize my memory timings and as much as it's annoying, it doesn't do any damage to the system.

And maybe don't overlock the CPU manually? Most Ryzen 3000-series chips don't seem to be all that happy being manually overclocked.


I have four sticks at 3800MHz, not had a single problem with it, but admittedly, I haven't run the system at full tilt hours on end. To be fair, it seems the memory subsystem is really solid this time around, as once all the UEFI/AGESA bugs were ironed out, I haven't had a single glitch with my system. In fact, I'm surprised it works as well as it does, compared to my previous Ryzen 7 1700 rig.

Well i mentioned it because memory can heat up quite a bit with the right kind of load , be totally stable in typical use and gaming, but put 100% of the right load on heat up beyond typical to an unstable state, especially if ambient heat is also high, ie high load pc crunching and folding in a small room ,then the heating kicks in.

 

[Bill_Bright]

Your attacking it from your perspective, which is right for you,

It is not what is right for me. I am attacking it from the most logical perspective. As a formally trained and certified electronics technician (as seen via the link in my sig) who has taught advanced electronics theory and troubleshooting, you always verify power first when troubleshooting electronics hardware. You cannot assume anything that depends on specific voltages is working correctly until you verify they are receiving those correct voltages. That's just basic electronics troubleshooting. It does not matter if this is a computer, TV, home theater receiver, a cell phone or a flashlight (or torch for you on the other side of the big pond).

And for the record, a simple meter will not do either. To test a computer PSU properly and conclusively it must be done under a variety of expected loads. This is because computers impose a variety of loads on their power supplies. Also, most multimeters cannot test for ripple or other AC anomalies that may be riding the DC output. Proper and conclusive testing of a PSU can only be done with sophisticated (and expensive) test equipment like an o'scope or dedicated power supply analyzer - not to mention the skillset to operate them, and technical knowledge to properly interpret the results. A meter is great for testing to see if a voltage is missing, but not a lot more.

Since most users don't have o'scopes or power analyzers, or the necessary skills, swapping in a known good supply is a tried and true option - even done by experts. This is why I always take a known good PSU with me on trouble calls.

 

[TheoneandonlyMrK]

It is not what is right for me. I am attacking it from the most logical perspective. As a formally trained and certified electronics technician (as seen via the link in my sig) who has taught advanced electronics theory and troubleshooting, you always verify power first when troubleshooting electronics hardware. You cannot assume anything that depends on specific voltages is working correctly until you verify they are receiving those correct voltages. That's just basic electronics troubleshooting. It does not matter if this is a computer, TV, home theater receiver, a cell phone or a flashlight (or torch for you on the other side of the big pond).

And for the record, a simple meter will not do either. To test a computer PSU properly and conclusively it must be done under a variety of expected loads. This is because computers impose a variety of loads on their power supplies. Also, most multimeters cannot test for ripple or other AC anomalies that may be riding the DC output. Proper and conclusive testing of a PSU can only be done with sophisticated (and expensive) test equipment like an o'scope or dedicated power supply analyzer - not to mention the skillset to operate them, and technical knowledge to properly interpret the results. A meter is great for testing to see if a voltage is missing, but not a lot more.

Since most users don't have o'scopes or power analyzers, or the necessary skills, swapping in a known good supply is a tried and true option - even done by experts. This is why I always take a known good PSU with me on trouble calls.

Tell you what ill leave you to help this guy, sorry bill.


Cannot be arsed arguing about any of this when were just trying to help a guy.

 

[AyoKeito]

No need to panic about the power button, it happens. Flick the switch on the PSU, leave the system for a bit and it tends to power right back up.

I don't have a problem with power button. If my PC would refuse to shut down i would just use a wifi power cord i have lying around and turn it off when i don't need my PC running. The problem is that i can't do work on my PC anymore because it hangs up minutes into rendering, while i've used to render for days straight. I just can't do anything meaningful in 10 minutes it allows me to work.
Power button is just a curious (and rare, i believe) symptom that may or may not point to the main problem.

And maybe don't overlock the CPU manually? Most Ryzen 3000-series chips don't seem to be all that happy being manually overclocked.

I am, in fact, aiming for lower voltages and frequencies with my "overclock" resulting in 10C cooler CPU and quieter fans. I wasn't really pushing it to the limit, quite the opposite. Anyway, PBO and Default CPU aren't working either.

Don't worry guys, i will switch both my RAM and PSU. I hear both of you

 

[Bill_Bright]

Cannot be arsed arguing about any of this when were just going trying to help a guy.

There's no need to be that way. As YOU correctly noted earlier, this problem "could" be one of many things. But if the car won't start, you don't replacing parts without first making sure there's fuel in the tank and the battery can turn the engine over.

 

[TheoneandonlyMrK]

There's no need to be that way. As YOU correctly noted earlier, this problem "could" be one of many things. But if the car won't start, you don't replacing parts without first making sure there's fuel in the tank and the battery can turn the engine over.

And as you pointed out you need quite expensive gear to properly test parts , substitution is fine, as i said ,do carry on.

 

[AyoKeito]

Okay, so it hang up during gaming again and won't boot, so my RAM tests are cancelled. I will hopefully get back to you in 24 hours with the result of PSU and RAM replacement. I'll also reassemble it on my desk just in case... The case is bad (pardon the pun).
Also, I forgot to tell you that after I plug the power cord back my motherboard lights up in a strange way. That only happens since crashes started. Google says nothing, bottom right is probably the chipset LED and the top one is not even listed in manual. Here's one bad quality picture.
I'll also contact ASUS to see what they have to say.
Thank you everyone for your assistance!

 

[toyo]

I've had this sort of thing happen to me twice, the first time it was a dying PSU, and the second time a dying GTX970 from Gainward. Each time the PC would blackscreen/lock without me being able to do anything other than hard reboot, until at one point it no longer booted at all. Curious what it will be the cause for you.

 

[Grog6]

There's a seperate processor that handles the startup process; it's in the support chip, what used to be the northbridge chip.

It loads parts of the bios code and ram to periphreal chips like the ethernet chips and other stuff, as well as read the power and reset buttons.

That's how you can update a bios without a cpu, in some cases.

Only a power supply problem or temperature can really corrupt that processors' operation; or extreme overheating of the northbridge chip.
Check it's temperature next time it crashes like that.

 

[Bill_Bright]

And as you pointed out you need quite expensive gear to properly test parts , substitution is fine,

Which is why substitution is often the only way for most people to verify if something is working properly, or not.

Also, I forgot to tell you that after I plug the power cord back my motherboard lights up in a strange way.

Your motherboard manual should tell you what the lights mean. Remember, when the power supply is plugged in (and master power switch set to on) it is still supplying +5Vsb standby voltages to the board.

 

[AyoKeito]

I've had this sort of thing happen to me twice, the first time it was a dying PSU, and the second time a dying GTX970 from Gainward. Each time the PC would blackscreen/lock without me being able to do anything other than hard reboot, until at one point it no longer booted at all. Curious what it will be the cause for you.

It's definitely not GPU since i've unplugged it while i was debugging, it didn't change anything.

Check it's temperature next time it crashes like that.

I've been logging all the temperatures and voltages via HWINFO before the last crash. But i can't get the log file since it's not booting. I don't think it's a chipset temperature because it was fine when i first started searching for a problem.

Your motherboard manual should tell you what the lights mean.

It actually doesn't. It mentions QLEDs (which are a set of debug BOOT, DRAM, CPU, VGA LEDs that light up (or don't, in my case) while the PC boots) and a 8pin LED which is off. It doesn't say anything about the LED near chipset or why would IO cover light up with red even if it's set to turn the LEDs off while PC is off.

I'm now 99% positive it's a PSU.
First of all: i've reassembled my PC on my desk as an open stand, used my old rusty 650W PSU that make strange noises while it works and it allowed me to encode for 30 minutes straight, that's when i got impatient.
I've hooked up my default PSU and PC didn't boot. It got stuck at DRAM QLED and i've tried 3 times. I've tried my old PSU again for sanity check and it worked. It also works right now while i make that post.
Another thing, and that's where i leave my other 1%: i'm using Thermaltake Sleeved Extension cables for all motherboard and GPU connections. The one that was going to 8 pin CPU is burnt. Plastic melted in some places. I suppose that's why i wasn't getting any QLEDs while 8 pin was hooked through it. When i got rid of it, i got at least DRAM QLED from my default PSU. Anyway, that means that both the extension cable and default PSU are now dead. I'm going to get a proper platinum Corsair PSU tomorrow and i'm not going to try my luck with more tests on old PSU.
Now, the only question is if there's any damage that burnt 8 pin cable did that i still don't know about... All the other extension cables are fine, but i think i'll get rid of all of them (the remaining 24PIN) except the GPU ones.

Thank you everyone!