Weird boot issue on Desktop PC

[RicHaj]

So, i'll explain this the best i can... here is the current situation of my pc.

 

When i power up the tower, all fans start running, there is no warning beeps or lights, everything SEEMS fine, except... the pc doesn't actually boot. There is no BIOS, no video, nothing.

Then, i power the tower off and immediately turn it back on again, and everything is fine. Like, perfectly fine. No hitchest, no issues, no freezes, pc can run 100% normally for multiple days with no issue.

 

I already did a through cleaning of the PC case, changed RAM, booted up with just one monitor ( usually i have 2 ) and with no GPU, but it's always the exact same issue.

 

My main concern here is that this is just a signal of another problem upcoming that i could prevent if i just learn what it is. But i have no clue at this point.

 

Any suggestions would be greatly appreciated. 

[paddy-stone]

OK, well I could be wrong here. But in my experience this is usually a video output problem, so in other words when you boot the computer and everything seems like it's running fine, it is in fact... you just don't get the video output, so you think it's not booted and power off the PC again.

I would try another video cable first off, next time you get this problem, swap the video leads, use a different input etc... again, I could be wrong, but when there has been no error code in POST, no beeps and everything seems like it's running... then I'd say it is running, you just can't see the output.

[SaladFingers]

If I had to make a quick guess, it's either your GPU or your PSU.

 

Does your motherboard have a LED indicator with post codes? Does it get stuck on a specific code?

[Guest]

A LONG time ago, I had a same problem. (with am AMD 1700+, which was OLD even then)

 

Computer would not start with BIOS boot. When it finaly started, all worked fine. In my case, the BIOS chip was old/worn out. (if I waited 30 minutes with power on, it would suddenly start booting) With my experiance, I would say: find a new motherboard, and check if the problem still exists, using your other exact hardware.

[Gonio]

Could be PSU or did you update Windows 10 by any chance?. OP use more specs in your post and also add them in your profile. Is more handy for us to respond without guessing what parts you use.