[SOLVED] Pc only starts after CMOS clearing!!!

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rodrigogamba

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Aug 14, 2018
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Hi everyone,
The thing is my PC was running normally at night, but the next morning when I turned it on, it began with a boot loop. The CPU cooler fan and the GPU fans started to spin for just 2 seconds, then the PC turned off and tried to start again, doing the same, getting in a boot loop until I unplugged the power cord. I tried to remove the entire hardware leaving just the PSU , and CPU, and I had the same trouble. I never get a beep because the PC never gets the POST stage.

Then I did a CMOS clearing removing the CMOS bottom cell, and magically the PC booted. I had to reconfigure MOBO time and date, and after a restart I finally could get on Windows, and the PC worked perfectly fine until I turned off. The same boot loop again!!!!! I did a CMOS clearing again but this time putting the CMOS JUMPER in pins 2 and 3 for a few seconds and putting back again in pins 1 and 2 with the PC turned of and unplugged. And it worked again!!!.

So I realized that Everytime I clear CMOS, removing de bottom cell or with the CMOS JUMPER , the PC boots normally. It goes through the POST stage, a little bit longer than normal, but finally it sounds the single beep that indicates that everything is good. First I get to the bios to reconfigure date and time, save changes and the then, After a restart, I can get into Windows.

I already tried changing the CMOS bottom cell for a new one, and still having the same problem.

Now, if I'd like to turned off my PC, I have to do a CMOS clearing every time I turned it on again.

I will be very grateful if you could help me with this.

My hardware
CPU: I7 4770k
COOLER: 212 EVO
GPU: Gtx 1080
RAM: 2 x 8 GB DDR3
PSU: Evga 750 +80 BRONZE
 
Solution
I tried to find the CMOS memory IC, but I really don't Know where is it. Could you help me to locate it? Coud be something like this?
https://es.aliexpress.com/item/32756151599.html
Nope. CMOS memory is either a standalone NVRAM ic or is contained inside SMC (system management controller), it acts similar to system RAM (needs power to maintain memory). The one you link is a BIOS ROM, it does not need power to maintain its content. I believe I wrote it up higher in this thread. It is usually located close to the battery plug but can be anywhere the manufacturer found some room to place it.
Test booting up without the battery - it should load up BIOS defaults every time.
Edit: I do not think the LGA 1150...
I tried to find the CMOS memory IC, but I really don't Know where is it. Could you help me to locate it? Coud be something like this?
https://es.aliexpress.com/item/32756151599.html
Nope. CMOS memory is either a standalone NVRAM ic or is contained inside SMC (system management controller), it acts similar to system RAM (needs power to maintain memory). The one you link is a BIOS ROM, it does not need power to maintain its content. I believe I wrote it up higher in this thread. It is usually located close to the battery plug but can be anywhere the manufacturer found some room to place it.
Test booting up without the battery - it should load up BIOS defaults every time.
Edit: I do not think the LGA 1150 board is worth the labor in this case.
 
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