I don't know how to adequately describe this in Google to find what I'm looking for. Maybe I'll have better luck here.

When booting up my desktop, it occasionally acts like it's about to boot up, doesn't even go into BIOS, monitor doesn't even light up, and then restarts; as in, it turns itself off and then on again. This happens rarely and randomly.

There's no humidity inside from what I can gauge, and everything seems to be plugged in OK. I don't for the life of me have the vaguest idea what might be causing it, and I'd rather find out now, instead of when something blows off a fuse and ends up costing me.

Windows 10, SSD, a year old. Never had this happening with anything else before. I've experienced dying motherboards, faulty hard disks, bad RAM, humidity, dust, etc with older computers. This problem is something new for me.

Any help would be greatly appreciated.

it sounds like something i experienced on a thinkpad.. possibly a mobo failure or corrupted bios chip. otherwise it could be a RAM issue. have you triied 1 stick of ram, swapping sticks and seeing if it corrects?

if it is a bios problem, you can check that out too, but you need special hardware to do it. you should be within warranty at 1 year. what type of bios chip is it, socketed or on the pcb?

Thanks for replying.

I'll have to check before getting back to you on the BIOS question. If it helps gauging what type of BIOS it might be, I didn't build the desktop myself. My laptop had died last year and I needed an urgent replacement for work, so this was a ready-built desktop (Lenovo).

Haven't checked anything with RAM. As this issue pops up randomly and rarely, I'll have no way of properly checking.

I forgot about the warranty. It should be good for another year. Still, it'd be great if I could be one step ahead (don't want this blowing up a week after warranty; looking at you HP).

I've had a similar issue happen with my system, which is a first generation Zen 1 CPU and motherboard. The problem with it is that technically, it should allow my RAM to run at 3200MHz, but it can't do that. This is something that plagued the first generation, and I don't remember if it has ever been established if it's the motherboard or the CPU that is causing this problem, since AMD and the motherboards manufacturers were both blaming the other ones.

Basically if I set my RAM speed to 3200MHZ from BIOS, sometimes my computer would start normally, and sometimes it would reset 3-5 times in quick succession, which would cause the BIOS to revert to default values, and finally be able to start, but with the memory running at 2400MHz.

Thanks, I like that idea, and it's easier to check.

A very obvious thing to try, but I don't see anyone mentioning it:
Update the BIOS. (IF a newer version exists)
(Especially a good idea when you have an old Ryzen with RAM/XMP(AMP) compatibility issues.)

That probably wouldn't manifest itself after a year of working fine. Wouldn't hurt to try, though.

Restarting like that is usually faulty power supply or motherboard, or both.

BIOS is up to date.

Kinda leaning towards the power supply idea, though I've experienced no other faults.

Thank you everyone for your suggestions.

I'll check BIOS, RAM, power supply. How can I check the motherboard?

By checking EVERYthing else... Most people do not have the spare parts to do that though.

Ah, there's the rub.

Do you have any other symptoms? Power supply is possible, but usually, I'd expect it to cause issues when the PC is under load. Have you stress-tested the CPU and GPU?

Otherwise, you could try to go down the tech support/warranty route given it's a pre-built. I'd suggest recording the fault though as anything that doesn't immediately manifest on a check is hard to get them to fix. I remember trying to return some RAM chips that weren't working properly - luckily I took a recording of the Memtest showing the failures as they tried to tell me that their Memtest didn't show any problems...

It may also be worth checking all cabling (data and power) throughout the entire PC, to make sure all is securely connected and pushed fully home (disconnect and reconnect), just in case something has failed or worked loose.

Ram chips are also worth checking too, as they can work loose from their sockets over time (eject and reseat each one).

Also check to see if all fans (power supply, CPU, GPU and case) are working and spinning freely, without obstruction.

I haven't properly stress-tested CPU & GPU, but I've been using it to render video, which brings up the temp considerably (more than any game). No hiccups there.

I don't know how I can approach the warranty route as I can't even properly describe the problem. Seeing as it is rare and random, there's no way of reproducing it.

Will have to check if everything is plugged in properly, as Trooper1270 suggested.

asus safe boot

is exactly what you describe.....

I have this experience when i plug off my pc from the electrical net, i do this quite often, during wkdays for example when i shutdown the connection on the insulated connector.

I can imagine this to happen more often on a older motherboard.

If the motherboard is not Asus from design or.... your motherboard does not have a safe boot feature then.... i personally would look into cooling options and indeed unplug all the cables on the motherboard and try them back in