Computer randomly shut down and won't boot + red spots occasionally on screen

[Lorenzilipe]

Hi, I've recently been having problems with the computer I built nearly a year ago. It has randomly shut down and I can't boot it up again.

First, I sometimes get weird red spots in dark areas of my screen. From my research it might be my graphics card or hdmi cable but it stopped happening, so not very concerned. The problem now is that I was loading the game Cities Skylines and my PC just completely shut down. I tried powering it back on again but it would turn on for about 15 seconds and then power back off again. I got it to run for about 2 minutes once, with the screen flashing at random intervals between black and lighter black and also got it to boot to my desktop once but it just shut down again.

I might be able to get it to work but I am really concerned if this could be a problem with my CPU or video card as I do not want to toast any of those things. Thank you very much in advance.

 

[MyHD4870x2Melted]

Is is shutting down or crashing?
Having artifacts show up on screen is a good sign it's not RAM or CPU related.
Your card could be going bad or you could be over heating.
Possibility even a bad connection with your motherboard.
If you have on board graphics, remove your card complexly and see if your computer still shuts down.

 

[Lorenzilipe]

Is is shutting down or crashing?
Having artifacts show up on screen is a good sign it's not RAM or CPU related.
Your card could be going bad or you could be over heating.
Possibility even a bad connection with your motherboard.
If you have on board graphics, remove your card complexly and see if your computer still shuts down.

I think it's shutting down, it just completely turns off as if I had pulled it out of the plug. I don't think the card is over heating though, but I might check connections to the motherboard. I've got a dedicated card by the way. Do you know what I can do next? Thanks.

 

[MyHD4870x2Melted]

LOL I guessed you had a dedicated video card, but if you also have an iGPU you can remove your dedicated card "completely" and boot from your built in igpu.
If every thing runs fine with a iGPU then you have narrowed it down to the dedicated card or the PSU
If your computer still shuts itself down then you at least know your card isn't the problem.

 

[Lorenzilipe]

LOL I guessed you had a dedicated video card, but if you also have an iGPU you can remove your dedicated card "completely" and boot from your built in igpu.
If every thing runs fine with a iGPU then you have narrowed it down to the dedicated card or the PSU
If your computer still shuts itself down then you at least know your card isn't the problem.

So yeah, I opened up my PC, pushed in my video card, checked all my cables, etc..., turned it on and it's working very perfectly. So the problem was actually a bad connection to my motherboard. Thank you very much.

 

[Lorenzilipe]

Open up your PC and check connections to motherboard, in my case, it was the graphics card, I believe.