# Black screen after a failed OC



## Leana (2 mo ago)

A week ago I bought a new graphics card (an RX 6600), everything was fine, I even overclocked it without any issues.
I decided to also mess with the processor (3600x) from the BIOS. The screen turned totally black, turning off the pc with the power button didn't work, neither did the restart button. So I did it with the back button.
When I turned the computer back on, everything seemed to start normally, except that the screen remained totally black (no signal at any point).

Since then I've tried the usual things, removing the battery (I left it out overnight), cleaning the CMOS with a screwdriver (+10 seconds), changing the RAM between slots, using only one RAM card, changing the graphics card between slots, changing the graphics card to the one I had before (gpx 1050), trying HDMI and DP cable, as well as trying another screen. The result is the same, the PC seems to turn on normally but no signal to the screen.
I looked at the manual of my motherboard (ROG STRIX B450-F GAMING) and I noticed that there is a light indicator that can give you an indication of what might be the source of the problem. After going from orange to red a few times, it changes to white and stays on permanently. Apparently it means it's a GPU error.
However, neither changing the graphics card slot, nor changing the graphics card for another one works. Both the fans on the 6600 and the GTX 1050 work, but only the 6600 keeps the fans running indefinitely, while on the gtx 1050 they stop working just after the white light comes on.

To me it seems to be either the CPU or the MOBO causing the issue.

The keyboard and all the lights in the PC turn on normally, but ctrl+alt+del doesn't work, so I think the operating system doesn't boot.

Any ideas?

Thank you in advance!


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## Corday (Mar 3, 2010)

Leana said:


> A week ago I bought a new graphics card (an RX 6600), everything was fine, I even overclocked it without any issues.
> I decided to also mess with the processor (3600x) from the BIOS. The screen turned totally black,


What exactly did you do?


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## MPR (Aug 28, 2010)

When you removed the CMOS battery did you also unplug the computer?


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## Leana (2 mo ago)

Corday said:


> What exactly did you do?


About the GPU I tried the default AMD adrenalin overclock, but finally decided to leave it as factory setting.

As for the CPU I initially used the EZ tuning wizard, it gave me no problems. Later I accessed the AI tweaker and changed some settings that I don't remember exactly as I don't have the menu in front of me, what I can say is that I didn't modify anything of the RAM or write values manually.
Sorry I can't be more precise!


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## Leana (2 mo ago)

MPR said:


> When you removed the CMOS battery did you also unplug the computer?


Yes, I also held down the power button.


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## MPR (Aug 28, 2010)

How much, if any, did you over-volt the CPU? Too much voltage can definitely damage a CPU.

Also, on the off chance that the problem isn't actually related to the overclock, you might go back into your case and re-seat all of your power and data cables, including those for the front-panel switches.


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## Corday (Mar 3, 2010)

I was about to mention voltage when MPR posted. Was the unit pre-built or a custom gaming computer?


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## Leana (2 mo ago)

MPR said:


> How much, if any, did you over-volt the CPU? Too much voltage can definitely damage a CPU.
> 
> Also, on the off chance that the problem isn't actually related to the overclock, you might go back into your case and re-seat all of your power and data cables, including those for the front-panel switches.


The highest option was 200 if I don't remember wrong. So that one.
Since I had already overclocked it using the AI, adding 200 on top of that could have been too much.
I would find it odd if it wasn't caused by the overclock, as the pc has worked fine for years, and the black screen happened right after the overclock.
I will try doing as you say anyway. Just in case!


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## Leana (2 mo ago)

Corday said:


> I was about to mention voltage when MPR posted. Was the unit pre-built or a custom gaming computer?


It is a custom computer. The 3600x has been working well for years.


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## MPR (Aug 28, 2010)

Did you leave your RAM settings alone or did you change them too? Improper RAM settings can also cause a black screen.


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## Leana (2 mo ago)

MPR said:


> Did you leave your RAM settings alone or did you change them too? Improper RAM settings can also cause a black screen.


I left the RAM alone.


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## Leana (2 mo ago)

I just made sure everything is correctly connected. Same outcome.
I removed the CPU to check that nothing was burnt. It looks in perfect condition, but I don't know if that means much.


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## MPR (Aug 28, 2010)

It may seem silly but just to check everything, is your monitor turned on?


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## Leana (2 mo ago)

MPR said:


> It may seem silly but just to check everything, is your monitor turned on?


Hahaha it's ok often big things are caused by small things
I tried two different monitors and made sure they were on.


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## Deejay100six (Nov 24, 2007)

Hi, and welcome to TSF.



Leana said:


> I would find it odd if it wasn't caused by the overclock, as the pc has worked fine for years, and the black screen happened right after the overclock.





Leana said:


> It is a custom computer. The 3600x has been working well for years.


As with anything electronics related, they do tend to work ok for years, but then suddenly...........they don't.


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## Leana (2 mo ago)

Deejay100six said:


> Hi, and welcome to TSF.
> 
> 
> 
> As with anything electronics related, they do tend to work ok for years, but then suddenly...........they don't.


Thank you for your welcome!! 
No doubt, but I've never had no clue of what's not working until this time. Should I buy a new cpu, a new mobo, maybe it's even the RAM... What about the power supply!? So many possible things!!
I still can't believe clearing the CMOS didn't work...


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## MPR (Aug 28, 2010)

Leana said:


> I still can't believe clearing the CMOS didn't work...


The best-case scenario would be to find a working computer with a compatible motherboard and try your CPU, RAM, and GPU to see if they all work. If they do, and your motherboard is getting power then it's the culprit.

Before doing anything else, however, I'd try once again to clear the BIOS information by unplugging the computer, removing the CMOS battery, and then short-circuiting the pins of CLRTC for ten seconds.

Note this:

"Except when clearing the RTC RAM, never remove the cap on CLRTC jumper default position. *Removing the cap will cause system boot failure!"*


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## Leana (2 mo ago)

MPR said:


> The best-case scenario would be to find a working computer with a compatible motherboard and try your CPU, RAM, and GPU to see if they all work. If they do, and your motherboard is getting power then it's the culprit.
> 
> Before doing anything else, however, I'd try once again to clear the BIOS information by unplugging the computer, removing the CMOS battery, and then short-circuiting the pins of CLRTC for ten seconds.
> 
> ...



Unfortunately I don't have access to another computer (I don't want to bother too much).
So you think the failure is likely to be from the motherboard?

I'll try clearing the BIOS again, thank you!

Sorry, but I didn't understand the last quote. What cap?


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## Corday (Mar 3, 2010)

A properly equipped shop can find the culprit.


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## MPR (Aug 28, 2010)

Leana said:


> Sorry, but I didn't understand the last quote. What cap?


That's from you motherboard's manual (section 1.1.6). However, a quick search reveals that Asus has changed it's CLRTC jumper configuration from a three-pin to a two-pin one. This is a printing artifact that was never removed from the manual when the hardware was changed.

I think that we are at the limits of the advice we can give over a forum. It's time now to decide whether or not the service and inspection fee of a computer shop is worth it or if you just want to apply it to new parts. The problem with playing "parts roulette" is that you really can't tell what's been damaged.

Personally, I'd first try disconnecting everything and then re-building the system while reading every page of the motherboard manual. This is why airlines are so safe -- pilots with thousands of hours of experience still follow checklists each and every flight. If nothing else, it will give a repair technician an exact idea of what you tried and what didn't work.

Pay special attention to beep codes. You will have to connect a speaker to the appropriate 4 pins of the system panel connector to hear the beep codes. Your computer case may or may not have come with a speaker installed so you will have to get one if it didn't. They are very inexpensive.


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## G_H_R (Dec 20, 2012)

Leana said:


> A week ago I bought a new graphics card (an RX 6600), everything was fine, I even overclocked it without any issues.
> I decided to also mess with the processor (3600x) from the BIOS. The screen turned totally black, turning off the pc with the power button didn't work, neither did the restart button. So I did it with the back button.
> When I turned the computer back on, everything seemed to start normally, except that the screen remained totally black (no signal at any point).
> 
> ...


Divide and conquer. Remove all external components including the CPU. Power on. Look at those status LEDs.
The one for CPU should light as fault. Add the CPU only. Setup the cooler correctly using correct thermal paste
of your choice. Power on again. CPU fault light should go off but RAM light should show trouble. Add RAM.
Power on again. RAM trouble LED should cease.

At this point plug the monitor to the mobo HDMI header or use DVI if that is possible. The GPU status light also indicates for integrated graphics. If it remains as trouble try resetting the BIOS again w/ only the RAM and CPU in place.

Plug in a keyboard. Do the lights flash on it when powered? Correct POST should poll the keyboard and light flash on/off. If the lights don't flash then control+alt+del won't work at all.

If after trying all of the above you cannot get an image there's one last Hail Mary. The Asus Flashback option.
Writes a new BIOS using a port on the mobo and should set it up correctly in case the RTC/BIOS clear is not.

[Motherboard] How to use USB BIOS FlashBack™? | Official Support | ASUS USA It requires access to another PC though to make a USB drive however.
I consider this as a last resort though since if you cannot get an image you have nothing left to lose.


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## jonnyb (May 23, 2006)

Leana said:


> A week ago I bought a new graphics card (an RX 6600), everything was fine, I even overclocked it without any issues.
> I decided to also mess with the processor (3600x) from the BIOS. The screen turned totally black, turning off the pc with the power button didn't work, neither did the restart button. So I did it with the back button.
> When I turned the computer back on, everything seemed to start normally, except that the screen remained totally black (no signal at any point).
> 
> ...


I love the statement: When I turned the computer back on, everything seemed to start normally, except that the screen remained totally black (no signal at any point). I would say that you fried the GPU.


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## G_H_R (Dec 20, 2012)

jonnyb said:


> I love the statement: When I turned the computer back on, everything seemed to start normally, except that the screen remained totally black (no signal at any point). I would say that you fried the GPU.


 Seems possible. 
Hence my advice to divide and conquer starting at the bare board, moving onto CPU, RAM, keyboard and integrated graphics. If the GPU is at fault, but integrated graphics work then the computer is at least usable and GPU is identified as source of the trouble. 

Could also be fine but mobo still going to integrated graphics first for the bios screen.


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## Leana (2 mo ago)

I finally decided to go to a repair shop. The motherboard was the culprit, he told me that some components on the motherboard had been damaged. He was able to replace them without having to swap out the whole motherboard.

In closing, I want to thank those who took the time to read me and tried to help me. And also to those who responded without reading.


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