Question Why is my PC turning on and off in a cycle? Why are my fans working but no the LEDs on the motherboard? Lastly, why am I not getting any video output?

[oversaltednoodle]

My Specs:
CPU: Ryzen 5 1600 65W AM4 Processor with Wraith Stealth Cooler
Mobo: ASRock B450M PRO4 AM4 Micro ATX
GPU: MSI GeForce GTX 1650 Super Ventus
Power Supply: EVGA 100-BR-0450-K1 450 BR, 80+ BRONZE 450W
RAM: GeIL EVO POTENZA 16GB (2 x 8GB) 288-Pin DDR4 SDRAM DDR4 3200
Case: Cooler Master MasterBox Q300L Micro-ATX

I am a new PC builder and I had recently built a PC based off of a YouTube video created by TechByMatt. Everything was going well until I booted it on for the first time. The power was going on and off in a 15 second cycle, the front io wasn’t working, I was getting no video output, and my LED lights on the motherboard were not turning on yet the fans were working. Anyone have any idea what the problem is? Also to note, when I took the parts out of the case last to use the bare bones cables (Mobo, graphics card with HDMI cable plugg ram, cpu with 24 pin connector, 8 pin connector, and PCIE 6 pin conenctor, connected to the power supply which is turned on and plugged into the wall) to get it running (because I’m an idiot who didn’t test it first) the same issue occurred.

 

[damian101]

Are you sure there are any LEDs on the motherboard that should turn on? The only LEDs, that the vast majority of motherboards have, are the LEDs from the Ethernet port, which often even glow when the system is turned off.
The motherboard could be dead. Or the CPU, but I think that's less likely.
Oh, and what do you mean with "The power was going on and off in a 15 second cycle"? It fails to post and powers itself on again?

 

[Steltek]

Is there any indication on the box or on the board itself what BIOS is installed? And, which specific model of Ryzen 5 1600 processor do you have (model number on the box should start with YD).

And, I presume you have double checked to ensure that the CPU cooler fan is plugged into the correct fan header on the motherboard?

Also, your memory modules are not on the manufacturer QVL list, so it could be a memory conflict (Ryzen CPUs can be picky about memory). You do have the modules installed in the A2/B2 slots? You might try with just one module in the A2 slot - if it doesn't work, power down and swap it for the other one and try again. If one doesn't work in A2 or B2, try one in the other slots as well.

 

[VirtualLarry]

Normally, Ryzen systems do not double-POST, like older P35/P45 Intel boards used to to set the chipset "straps". However, if the DRAM is not "training" properly, some/most Ryzen mobos, will do a sort of soft reset several times, possibly with successively looser timings, to attempt to get the DRAM to work. If that fails, then it may reboot entirely, and then you're probably stuck at a black-screen.

Do you have a "beeper" (piezo speaker) attached to the mobo? It should beep at you. (Single light beep is correct POST. Multiple beeps are errors.) Some mobos have diag LEDs somewhere on the board, for CPU/VGA/RAM/BOOT. Those can also help diagnose, if present.

I would try a different kit of RAM, or clear CMOS (if you haven't already), and just try to POST with JEDEC timings (don't go into BIOS and set XMP, yet).

Generally, with most Ryzen mobos, you use the 2nd and 4th RAM slot, for a single dual-channel kit (two DIMMs).

 

[ElFenix]

sounds like you have a short.

take it out of the case. check the case to make sure you don't have any extra standoffs (the screw in mounting points) under the board that aren't being used to hold it in, or something like a screw lost behind the board.

put the board on top of the motherboard box (anything non-condctive, but the box works good), leave in the CPU with its fan, and 1 stick of ram. no graphics card, no other ram sticks, nothing. make sure the ram is plugged all the way in. clear the CMOS following the instructions in the motherboard's manual (looks like you short the jumper pins that are between the two bottom fan connectors and the USB 2 headers on the board, if there's no jumper there hold a screwdriver to the pins without power to the board).

plug in the power supply, and short just the power switch pins for the front panel connector with a screwdriver. it should boot, which you'll know because the CPU fan will spin up and stay spinning. assuming that works, add other parts one at a time. turn the power supply off using the switch each time. i would try each stick of ram in each of the slots just to make sure that it works.

 

[DAPUNISHER]

Since you already booted bare bones, try this: Pull all power from the board and vid card. Pop the CMOS battery out, and while you are at it take out the ram in B2, as was suggested. We only want one stick of ram for now. Go do something else for 30 minutes. Put the battery and power cables back in, and short the power pins. If it starts cycling again, let it do it at least 8 times. The training thing Larry mentioned can take a bit. I had a B350 Tomahawk take that many cycles a while back. If no joy, turn the PSU off, and swap ram, but still use A2 slot. If still no joy, try the 1650 Super in the other PCI-E slot. If it still won't post and make it to UEFI, I would exchange the board with the vendor you bought it from.

 

[Steltek]

The reason I asked about the BIOS revision and chip model is that there are actually two different versions of the Ryzen 5 1600. One is based upon the original Zen architecture, the other is based upon the newer Zen+ architecture refresh (which is the one somebody is most likely to get if they buy one today).

While your motherboard will run the original Zen-based CPU at all BIOS levels, it will only run the newer Zen+ based revision if the BIOS is at least P2.00 or higher. If you somehow have gotten an old stock board with original BIOS and a Zen+ based CPU, it won't work without a BIOS upgrade.

 

[ElFenix]

The reason I asked about the BIOS revision and chip model is that there are actually two different versions of the Ryzen 5 1600. One is based upon the original Zen architecture, the other is based upon the newer Zen+ architecture refresh (which is the one somebody is most likely to get if they buy one today).

While your motherboard will run the original Zen-based CPU at all BIOS levels, it will only run the newer Zen+ based revision if the BIOS is at least P2.00 or higher. If you somehow have gotten an old stock board with original BIOS and a Zen+ based CPU, it won't work without a BIOS upgrade.

if the board box has the "AMD Ryzen 3000 desktop ready" logo on it, it should have a bios that can boot that chip