Monitor is blank/no signal

My PC was running fine this morning, but when I tried firing it up this afternoon, it sounds like it's booting, but the monitors stay black. I’ve already tested two different screens using both HDMI and DisplayPort cables, but nothing works.
I tried swapping the RAM sticks one by one in every slot, cleared the CMOS, and even pulled the battery, but no luck. I also tried reseating every single cable just to be sure.
The RGB on my keyboard and mouse used to light up the second I turned the power on, but now they stay completely dark. Does this mean my motherboard is dead?

First thing you gotta do is check the graphics card, then look at the power supply in your rig.
Maybe try using the integrated graphics on the motherboard—just pop that card out of the PCIe slot and see if you get a picture on the screen...

Plus, just strip everything back—yank out all the cards, pull the drives, pop the RAM, and unplug every single peripheral you've got. If it doesn't beep at you and stays dead quiet, then you're looking at either the motherboard or the CPU. You could even try swapping out the processor if you're feeling brave enough, but if it still won't make a sound after that, the motherboard is definitely toast. But hey, if it actually starts beeping? Then you know it's the CPU.

Jack Cook7 said:Also, pull out all the cards, drives, and RAM, then unplug everything else. If it doesn't beep and stays silent, you're looking at the motherboard or the CPU. You can try pulling the processor if you're comfortable doing that; if there's still no beep, it's the motherboard. If it does beep, it's the CPU.

Do I really need to take it apart, or can I just unplug the power supply?

Zachary Nguyen2 said:Do I seriously need to pull the whole thing out, or can I just unplug the power supply?

Good grief...

First off, kill the power to everything—unplug that 120V line from the wall.

Then, call up that one tech-obsessed friend of yours. While you're geeking out over the new season of Mandalorian, casually—you know, totally by accident—ask him if he knows a solid PC repair shop or a specialist who handles power supplies. Keep it low-key.

Jack Cook7 said:Good grief...

First things first, just unplug that 110-volt power supply from everything.

What's the deal with those armor plates? 😁

Then you should probably give that hyperactive geek friend of yours a call, and while you're catching up and geeking out over the new season of Mandalorian, just casually—you know, totally discreetly—ask him if he knows a solid PC technician who specializes in power supplies.

Haha, you're hilarious😁

First off, that beeping doesn't necessarily mean much, but here's my take on what's going on:

- Based on the symptoms, it's almost a certainty that a component within the power supply gave up the ghost, even if the computer sounds like it's running fine. Your best bet is to grab a spare power supply or borrow one to test it out; if swapping it in gets the system running smoothly, then you've found your culprit. If you can borrow one from a buddy, do that, and if it works, it's definitely time to go out and buy a new one.

Until you actually try that, I wouldn't jump to the conclusion that the motherboard is the issue, though this whole situation feels a lot like a failing graphics card. But since your RGB keyboard isn't even lighting up, I'd say it's most likely the power supply without a doubt.

Man, where do these smart kids on Reddit even come from?

God forbid they actually learn how to be funny and entertaining—what's left for us old-timers then?

swiftowl7 said:What about the armor? 😁

Haha, you're crazy. 😁

First off, the beeping isn't necessarily linked, but here's my diagnosis:

- Based on the symptoms, it’s almost certain a part of the power supply died (even if the PC sounds like it's running). Your best bet is to grab a spare PSU and swap it out to test it. If the computer boots normally with the new one, you found your culprit. Just borrow a unit for testing, then buy a new one if it works.

Until you try that, don't assume it's the motherboard. It looks exactly like a GPU failure, but since the RGB keyboard won't even light up, it’s definitely the power supply.

The RGB keyboard lights up when I turn the PC on.

Jack Cook7 said:Good grief...

First, unplug the power cord from the wall.

Then, call that crazy geek friend of yours. While you're chatting about the new season of Mandalorian, casually ask him if he knows a good PC technician who handles power supplies. Keep it low-key, obviously.

I was talking about the CPU power cable going into the motherboard.

Zachary Nguyen2 said:The RGB keyboard lights up as soon as I boot the PC.

It doesn't really matter right now because before we can even start guessing, we have to rule out the power supply, since everything starts there.

If a single voltage rail on the PSU is acting up, you'll see it everywhere—the motherboard won't behave, you might not get any BIOS beeps, and parts of the system just won't kick over. It’s a lot to explain, but it's all connected.

A failure like yours usually points toward the PSU, the motherboard, the GPU, or the RAM, and none of those components are particularly cheap to replace, especially if you're looking at a combination of two or more failing at once.

swiftowl7 said:It doesn't change much. We have to establish first that you can't just guess blindly that it isn't the PSU—everything starts there.

If a single voltage rail on the PSU fails, neither the motherboard nor the system will behave right. It won't beep or even start parts of the PC. It’s complicated to explain.

A failure like yours usually hits the PSU, the motherboard, the GPU, or the RAM. None of those parts are cheap, and it could be a combination of things.

Yesterday, it actually booted once—I reached the Windows screen—when I put one stick of RAM in the fourth slot. Then I shut it down, swapped in the second stick, and still no picture. I went back to just the one stick in the fourth slot, and still nothing.
I thought it was the RAM, so I bought new RAM, but nothing changed. It's the same issue, so it's definitely not the RAM.

swiftowl7 suggested that the power supply unit is the culprit.
Every symptom you've described points directly to that conclusion.
The machine might actually boot up once in a while, but its reliability is entirely questionable at this point. You could attempt to run some stress tests to monitor the voltage or check the readings within the BIOS, but frankly, the most logical course of action is simply to purchase a new one.

I'll try it on another PC and then plug it back in.

So, what kind of power supply (brand and model) are we talking about, and what else is in the build?

fadedorca66 said:What power supply are you using (make and model), and what else is in the build?

EVGA Supernova 550W G2 80+ Gold
Ryzen 5 1600
Kingston HyperX Predator 2x8GB 3200MHz
Sapphire Nitro+ Radeon RX 580 4GB
Gigabyte ga-ab350

I tried the paper clip test on the EVGA unit and it seems fine, though that doesn't rule out a PSU issue. I also swapped the GPU cable, but still nothing.

Zachary Nguyen2 said:Evga supernova 550w g2 80+ gold
Ryzen 5 1600
Kingston hyperx predator 2x8gb 3200mhz
Sapphire nitro+ radeon rx 580 4gb
Gigabyte ga-ab350 gaming

I tried the paper clip test on the Evga unit; it seems to spin up fine, though I realize that doesn't rule out an underlying issue with the PSU. I also swapped the PCIe cable to the GPU just to be sure, but still nothing.

🤦 I honestly don't understand why you refuse to listen to basic advice. Using a paper clip might jumpstart the power supply, but if the voltage rails are unstable or incorrect, the system simply won't boot.
It is the equivalent of checking your tire pressure because your car won't start...
it is frankly hard to believe some people are this dense. You claimed you could walk over to another PC within two minutes and know exactly what was happening.
Electronic components are not immortal; they degrade over time, particularly if the manufacturer cut corners with cheap capacitors or pushed the voltage and current limits too close to the edge—not to mention the frequency stability of an SMPS. What you actually need to verify is the voltage and current delivery. For $20 you can pick up a multimeter that clips onto the connector to show you the readings, though keep in mind it won't show you how it performs under a heavy load...

Jerry Robinson56 said:🤦 why aren't you listening to advice? You can jumpstart a power supply with a paperclip, but if the voltage isn't right, the system won't run.
It’s like checking your tire pressure because your car won't start...
I honestly can't believe some people are this clueless... you claimed you could get to another computer in two minutes and know everything.
Electronic components don't last forever. They degrade over time, especially if the manufacturer used cheap parts or pushed the voltage and current limits too far—not to mention SMPS frequency issues... what you actually need to check is the voltage and current. For $20, you can grab a multimeter, hook it to the connector, and see everything, though it won't show you how it performs under load...

I can get to another PC, but it'll take me a week.

Zachary Nguyen2 said:I can swing by with the other PC, but I won't be able to get there for about a week.

Alright, if you can make it happen, here’s my suggestion:

- Just grab a new power supply. Honestly, even if the PSU isn't actually the culprit this time around, it's still a smart move. Don't bother returning it to Best Buy; just tuck it away in a box in your closet as a spare for later.

With high-end gaming rigs, power supplies tend to burn out eventually anyway, so you might as well stay ahead of the curve. From what I gather, you'll probably need one that has that 6-pin molex connector.

The best way to handle this is to pull out the current PSU you're using and take it with you to the shop so you can match it up perfectly.

I wouldn't just jump to conclusions about the power supply, especially since you're using a decent unit that probably isn't even that old (relative to the rest of your build).

It feels like your motherboard might be acting up. Try popping just one stick of RAM into slot one (check your manual, I think it's actually slot two), clear the CMOS, and then just keep restarting it a few times. Maybe that’ll force it to boot from the backup BIOS if the main one is being stubborn—most boards have a secondary one for when things go south. What BIOS version are you running on that board? If it's an older version and you can actually get it to post, maybe try flashing a newer one.

I actually have the same motherboard and mine glitched out right after a BIOS update. I had to clear the CMOS and just keep rebooting until it finally decided to behave.

fadedorca66 said:Well, I wouldn't be so quick to dismiss the power supply, especially since we're talking about a high-quality unit that likely isn't nearly as old as the rest of the build.

It seems to me that your motherboard might be acting up. Try installing just one stick of RAM in slot one—check your manual to confirm which one that is, though I believe it’s slot two—then clear the CMOS. If it doesn't boot immediately, try restarting it a few times; you might need to force it to trigger the backup BIOS if the primary one fails to initialize. Most modern boards have a secondary BIOS for exactly this reason. What version is currently running on the board? If it's an older version and you manage to get it to post, you should attempt to flash a more recent BIOS update.

I have the exact same motherboard, and mine glitched out right after a BIOS update. I had to clear the CMOS and cycle the power several times before it finally stabilized.

The configuration is solid regardless of its age, but one should always opt for at least a 750W power supply to ensure adequate headroom and stability during transient spikes, whether for heavy workloads or marathon gaming sessions. I leave my rigs running through the day to mine crypto—I have a "descendant" like that... he's actually a moderator on a major English-language gaming site.🤦

The input capacitors are under the most stress, but the issue could also lie within the MOSFET gate capacitors or the controller chip itself when transitioning from standby to active mode.

You would have to agree that checking the power supply is the logical first step. Since the user can't easily test that here, there isn't much else to suggest beyond the BIOS reset mentioned earlier.
The RX 580 series cards are incredibly resilient; I own both the 4GB and 8GB versions, and they have performed flawlessly for years, running at least 12 hours a day without fail.
It is worth noting that all power supplies draw from the same internal rail regardless of the connector type, but you can still encounter issues where a contact is poor or oxidized, even if the PC has been sitting idle in a room. I dealt with a case like that once; a Molex connector scorched and left a nasty black mark, making the diagnosis instant.

Now that I see the board has a DVI port, just pull the graphics card out and plug directly into the motherboard. After all, Duke pointed out exactly that. 👍
Unless the motherboard is completely dead, the solution should be obvious. Testing the power supply remains the most cost-effective and primary troubleshooting step.