System doesn't POST

[Semper]

The circumstances:

In the process of overclocking. Testing what I felt was a stable overclock (4.3GHz, forgot voltage), Prime95 had been running for about 8 hours. temps were fair, not great due to the area I live in, but within operable range, average was around ~70, high was no more than 81 according to CoreTemp 

This system is almost three years old, has been running stable since assembled, never overclocked until yesterday.

 

Specs can be found in my signature

 

The problem:

While stress testing the overclock with P95, my screens just went blank. system remained operational (case fans were spinning, GPU fans were spinning, PSU fan was spinning) however both monitors just went blank. Since then, system does not post. It powers on, all fans spin up, but it does not post, monitor does not detect an input signal. Tested GPU with an older one known to be working, same result.

 

What i've attempted:

Removed H80, cleaned thermal paste from block and CPU, inspected for visual damage (none was observable) re-pasted and re-mounted. checked RAM. all sticks are visually OK, tested sticks individually, still no post.. Tested GPU (as stated above). opened up PSU, inspected for any visual damage, none present. checked every single connection both inside and out of my case, all are OK.

 

I'm assuming i've either fried my CPU (perhaps CoreTemp was giving of false readings?) or my motherboard. 

If anyone has some troubleshooting tips, they'd be greatly appreciated. I'd prefer to go through five hours of troubleshooting to find that it's my PSU and save the $500 on a new board/processor, or, only have to replace one of the two.

 

The faster I can get this system up, the better, it's needed for school.

 

Any help is greatly appreciated,

many thanks guys!

[jezza39]

Does your mobo have a POST LED readout? Or somewhere to connect a speaker too so the mobo can output an error code? It could be your motherboard or the CPU, I believe AMD CPUs don't like going over 60 while Haswells on teh intel side can handle ~100.

[Semper]

Does your mobo have a POST LED readout? Or somewhere to connect a speaker too so the mobo can output an error code? It could be your motherboard or the CPU, I believe AMD CPUs don't like going over 60 while Haswells on teh intel side can handle ~100.

Unfortunately, no. It has no readout.

i'd have to double check on the speaker, however if I recall correctly, it does not. I"ll get back to you on that one shortly.

My CPU regularly runs over 60, In fact the Bulldozer is somewhat known for running hot. I do have my system setup for thermal protection, it'll shut itself down if it reaches 90.

[nanowatt]

 

I'm assuming i've either fried my CPU (perhaps CoreTemp was giving of false readings?) or my motherboard. 

Amd is known for it's trouble with the temp sensors(always use a temp warning or shutdown when it reaches about 90degrees).Most likely the cpu is dead but not because of the heat but because of the stress test.It may be the mother board too but if very unlikely.A cpu can run fine at 100 degrees without killing itself so quick.If you ever had to change old processors you know that if the model is not on the support list it won't post.So yeah...i think you get my point

[nanowatt]

did you clear the cmos?or restarted the bios to get rid of the oc settings?

[jezza39]

Pull the mobo out, have a close look at the chokes and phases for burn marks, any unusually blackened areas will point to a burnout on the mobo. I read that 60 is the limit, but I have no experience with AMD CPUs so take my words with a grain of salt on this. 

 

Usually a mobo will burn before the CPU so have a look.

 

I know the GA-X79-UD4 has no LED readout but a speaker connector so have a look. A speaker is far more basic than a readout.

[nanowatt]

Pull the mobo out, have a close look at the chokes and phases for burn marks, any unusually blackened areas will point to a burnout on the mobo. I read that 60 is the limit, but I have no experience with AMD CPUs so take my words with a grain of salt on this. 

 

Usually a mobo will burn before the CPU so have a look.

 

I know the GA-X79-UD4 has no LED readout but a speaker connector so have a look. A speaker is far more basic than a readout.

usually dead cap or mb won't let the pc start simply because if there's a short in the circuit the psu will detect it and stop the power

[Semper]

Much to my surprise, I do have a point for my speaker...

as soon as I find it, i'll let you know my results.

 

@nanowatt. I didn't know AMD had issues with their temp sensors..

I do have a warning and a shutdown. warning is at 88, shutdown is at 90, system worked as I tested on assembly (three years ago, mind you) warning popped up, and the system shut down about 30 seconds later.

 

CMOS was cleared

 

MoBo was pulled, no visual damage to the board anywhere. Forgot to mention that part.

[jezza39]

usually dead cap or mb won't let the pc start simply because if there's a short in the circuit the psu will detect it and stop the power

 

Wow never knew that, thats actually pretty cool.

[nanowatt]

Much to my surprise, I do have a point for my speaker...

as soon as I find it, i'll let you know my results.

 

@nanowatt. I didn't know AMD had issues with their temp sensors..

I do have a warning and a shutdown. warning is at 88, shutdown is at 90, system worked as I tested on assembly (three years ago, mind you) warning popped up, and the system shut down about 30 seconds later.

 

CMOS was cleared

 

MoBo was pulled, no visual damage to the board anywhere. Forgot to mention that part.

You fried the poor processor.YOU merciless beast!

[Semper]

You fried the poor processor.YOU merciless beast!

Is, unfortunately, what I fear(ed).

I think i'll stick to stock voltages... overclocking doesn't seem to go well for me

[nanowatt]

Wow never knew that, thats actually pretty cool.

Industrial grade protection: OVP (Over Voltage Protection), SCP (Short Circuit Protection), and OCP (Over Current Protection)

[jezza39]

Industrial grade protection: OVP (Over Voltage Protection), SCP (Short Circuit Protection), and OCP (Over Current Protection)

 

Ahhhhh I thought OVP & OCP were upstream protection from surges on the AC in line and SCP was some internal stuff. Learn something new everyday thanks

[Semper]

Well... a replacement FX-8350 should be on it's way some time today. I guess i'll mark this one as solved, and hope it's not my Motherboard, or CPU and Mobo.

Thanks guys!

Oh, and there's no audible sound for a POST with my speaker.