[SOLVED] AMD FX8350 One Core Broken

[riobear1]

Hello,

I've built a couple of computers before but have an issue which is persistent. As you know FX8350's have 8 cores in total. One of my eight cores are failing as my computer will regularly blue screen with system thread exception not handled and a few other BSOD's. I have absolutely no idea what to do.

https://valid.x86.fr/vlmxeh - The specs of my computer.

If you require more info just let me know.

Thanks in advance.

[fastcar123]

As unfortunate as it is. If you want to save the cpu you could try to disable 2 cores. It would make it a 6 core cpu but you could probably still use it.

 

Theres a chance though, that if your Bios disables 2 working cores. In which case you may be out of luck

 

Another thing to try is a clean OS install and an update chipset driver.

You could also update the bios as well.

[Levent]

1 minute ago, fastcar123 said:

As unfortunate as it is. If you want to save the cpu you could try to disable 2 cores. It would make it a 6 core cpu but you could probably still use it.

 

Theres a chance though, that if your Bios disables 2 working cores. In which case you may be out of luck

 

Another thing to try is a clean OS install and an update chipset driver.

You could also update the bios as well.

wat.jpg

OP: we need to see full bluescreen dump ,check this out 

 

[riobear1]

Thanks for the quick response.

At the moment I've disabled a core. By the looks of it it's a logical core that's broken, because if a physical core had broke it'd blue screen but I experience nothing. I have installed windows a few times and had disabled them with windows because I only want one core off as it affects blender speeds and I do rendering.

[AvocadosGuac]

How can the logical core be broken but the physical one not? This doesnt make any sense...

 

Make it simple for us. What do you want?

[iamdarkyoshi]

What happens with a severe downclock? Wondering if its unstable or just completely dead.

[riobear1]

1 minute ago, Levent said:

wat.jpg

OP: we need to see full bluescreen dump ,check this out 

Windows 10 Pro

x64

Windows 10 Pro

Full Retail Version (has appropriate drivers for motherboard etc.)

Nearly a year old (made in August around the 20th)

OS is around 3 days old as I had tried to fix the issue hoping it was a small corruption

FX8350 Black edition

HD5450

Gigabyte 970-DS3P

Unsure - 750W

Home Built

NA

Desktop

I can't give PerfLogs because I deleted the volumes for the clean install.

 

 

[System Error Message]

fx has no logical core. Each core is a real core, each 2 cores share float units.

 

your problem might not entirely be CPU though. If a CPU was broken you would not get a bluescreen, you'd get a hang or instant restart or shut down.

 

2 possibilities.

First is the board's VRMs and power deilivery could be bad or it could be the PSU is out of spec and crappy. Temperature could also be an issue too.

 

Second could be ram. Rendering on all 8 cores (4 actual for rendering but 8 for non float or large dataset math tasks), could be stressing the ram out revealing the ram to be faulty. Run memtest to verify.

[riobear1]

I am simply looking to see if anyone has any recommendations as I'll struggle if not be unable to send it back to amd because we have no receipt to hand and by the time we find it it'll be out of warrenty if not already.

 

Also I have never downclocked my CPU but I doubt it'd be unstable or dead.

Edited August 12, 2017 by riobear1
Response to someone

[riobear1]

2 minutes ago, System Error Message said:

fx has no logical core. Each core is a real core, each 2 cores share float units.

 

your problem might not entirely be CPU though. If a CPU was broken you would not get a bluescreen, you'd get a hang or instant restart or shut down.

 

2 possibilities.

First is the board's VRMs and power deilivery could be bad or it could be the PSU is out of spec and crappy. Temperature could also be an issue too.

 

Second could be ram. Rendering on all 8 cores (4 actual for rendering but 8 for non float or large dataset math tasks), could be stressing the ram out revealing the ram to be faulty. Run memtest to verify.

It's not ram I ran a test and found no issues when I did. Onto the idea of a power delivery issue I have an issue where my PC turns on, off and back on before booting up fully. Could that show that there may be a Mobo or PSU issue?
I have a spare PSU to hand which has the right wattage however I believe it may be faulty as I fixed a broken PC and swapped the psu out. I could possibly use it if need be.

[BWLServers]

That's verrrrrrrrrrrrry odd for a single logical thread to die. That means half of one FX core died.

I've never ever ever ever heard of such a thing happening....
Not to say it's not possible. Just extremely intriguing if that is indeed what happened.

[System Error Message]

2 minutes ago, riobear1 said:

It's not ram I ran a test and found no issues when I did. Onto the idea of a power delivery issue I have an issue where my PC turns on, off and back on before booting up fully. Could that show that there may be a Mobo or PSU issue?
I have a spare PSU to hand which has the right wattage however I believe it may be faulty as I fixed a broken PC and swapped the psu out. I could possibly use it if need be.

that isnt a PSU issue, its a board issue. Still testing with another PSU could help. Look at your motherboard, do you see the arrangement of cubes and capacitors around the CPU to have gaps? Like rather than a nice uniform close looking arrangement of cubes and capacitors you see uniform gaps where you could fit cubes and capacitors in the gap? If you see such gaps that means your board is either missing components or not very good.

 

Temperature is an important factor too. Higher temps on board, not so good for VRMs or even the bus. Higher CPU temps, not so good on the CPU itself. The fx should not exceed 80C. Below 70C max is good.

[riobear1]

Just now, BWLServers said:

That's verrrrrrrrrrrrry odd for a single logical thread to die. That means half of one FX core died.

I've never ever ever ever heard of such a thing happening....
Not to say it's not possible. Just extremely intriguing if that is indeed what happened.

I may be wrong but windows is running fine on 7 threads instead of 8 so God knows what's going on. However I have a gut feeling which is hinting that it's a logical one rather than a physical one (however I haven't much knowledge on how a logical one works)

[BWLServers]

On FX CPUs, there are "8" cores. 4 typical cores with another inline "forked" core that shares the resources. So it's a bottlenecked 8 core essentially.

[BWLServers]

That's why they're smashed on so much as they aren't true 8 cores.

[System Error Message]

4 minutes ago, BWLServers said:

That's why they're smashed on so much as they aren't true 8 cores.

actually i would not say thats the case. The fx makes a good CPU if you arent rendering or doing math with it. From my experience the lga 1366 is almost twice as fast IPC wise when it comes to math, physics, 3D and such, things that require the use of the FPU, SSE and so on. This i found out in single core loads btw. The lga 1366 is the first intel iseries and the only intel iseries platform that lets you overclock and tweak locked CPUs to a huge extent. You could take a xeon CPU in a desktop LGA 1366 board and overclock it near double the speed despite the locked multiplier. So given that both platforms will run past 4Ghz, the fx is slower by a huge margin, about half the speed of the iseries per clock for anything that relates to the FPU, SSE and so on. Apparently gaming and rendering performance gives more fame to a CPU so it was bashed on only because it was slow at these tasks. It was not really that the resources were shared, it was just slow at the things people consider a fast CPU to be good at. The fx is fast at other things though.

[Tiwaz]

the cpu needs a lot of power and isnt the newest so i dont think it would be far fetched to claim that one core has died or even one cluster which consists of two cores. Like others have said, if it is possible to disable cores then maybe you can disable the one that doesnt work, its probably not one of the first four cores since then you wouldnt be getting into windows at all. Maybe your CPU just got unstable on one core and you could either lower the multiplier by 1x or increase Vcore 

[riobear1]

I'll be offline until tomorrow and will be doing some possible repair attempts tomorrow. Thanks so much for the support so far.

[riobear1]

Just now, Tiwaz said:

the cpu needs a lot of power and isnt the newest so i dont think it would be far fetched to claim that one core has died or even one cluster which consists of two cores. Like others have said, if it is possible to disable cores then maybe you can disable the one that doesnt work, its probably not one of the first four cores since then you wouldnt be getting into windows at all. Maybe your CPU just got unstable on one core and you could either lower the multiplier by 1x or increase Vcore 

I'm afraid to say I never changed vcore and my CPU is currently stable on 7 cores instead of 8.

[Tiwaz]

Just now, riobear1 said:

I'm afraid to say I never changed vcore and my CPU is currently stable on 7 cores instead of 8.

well yeah, one core's silicon is worn out a bit more, that can happen over time, so try a small bump in Vcore voltage and check again, might be just that. Add 0,010V and try if it is stable and add more if its not enough

[System Error Message]

silicons dont wear out. unless however they were overvolted past their safe voltage before as CPUs disintegrate (see the 1.8V and pentium 4 for reference). Otherwise its usually a power issue or perhaps the core could've been physically damaged (delided)

[Bananasplit_00]

8 minutes ago, riobear1 said:

I may be wrong but windows is running fine on 7 threads instead of 8 so God knows what's going on. However I have a gut feeling which is hinting that it's a logical one rather than a physical one (however I haven't much knowledge on how a logical one works)

... Look. There are no "logical" cores as you are implying. A logical core would be a thread and all physical cores make up a thread but there is also hyper threading which creates extra threads and therefore they are purely logical cores. FX processors have no HyperThreading/SMT and therefore no purely logical threads that can break. Only physical ones. FX has its cores stuck together in pairs so a single physical core breaking without the second one also breaking would be almost impossible, or at least extremely rare. I haven't got the slightest clue what your problem is though. 

[riobear1]

So I started my repairs.

I changed PSU

I added a fan (opted to for lower temps)

I re-installed the ram

and took out the cmos battery for 10 seconds which did nill (I'm going to try shorting the reset pins like stated in the manuals ("No one reads manuals", "If your setting up a watercooling block for a graphics card read the manuals!" - Linus tech tips)

 

Also this failed one core still fails

[MightyBooty :^)]

10 hours ago, riobear1 said:

So I started my repairs.

I changed PSU

I added a fan (opted to for lower temps)

I re-installed the ram

and took out the cmos battery for 10 seconds which did nill (I'm going to try shorting the reset pins like stated in the manuals ("No one reads manuals", "If your setting up a watercooling block for a graphics card read the manuals!" - Linus tech tips)

 

Also this failed one core still fails

970a-ds3p is a board with very weak vrm engineering, should not be used with an 8-core even running stock clocks my MSI 970a-g46 is similar in engineering *shitty* and can only handle a 6300 otherwise it overheats past 80c on the mosfets with the extra cores of the 8000 series and that's with a fatass noctua cooler blowing down heavenly rays upon the shite vrm. You'd probably have to manually increase voltage over stock to rid yourself of the system thread exception as it's almost 100% that your board is not supplying the cpu with enough voltage either from overheating vrm or stock auto settings are incorrect for your cpu. Btw the fx series are all true cores, just they share fpus. Intels architectures work in a similar fashion which is why they were getting so much flack from intel when the cpus came out. 

[Nena Trinity]

Disable the damaged core or if you most the entire module...