PC won't boot up

I was just mindlessly scrolling through the news and wasting time online when my PC suddenly died on me. Out of nowhere, the monitor flashed "Entering sleeping mode," and then... nothing. Total blackout. I’ve already gone full technician on it—ripped the whole thing apart, cleaned out all the dust, and reassembled everything—but it still won't boot up. I actually saw that "Entering sleeping mode" message once a while back, but at least then I could get it back up and running immediately. This time? Dead air. The monitor itself seems fine; the power light is on, but it just keeps displaying "No video input." It’s like the tower is refusing to talk to the screen entirely.
What's my next move?

Not even a single LED on the PC?

It looks like you might be dealing with a faulty power supply if the PC won't even boot up.

Alright, I just popped the case open and gave it a shot. When I hit the power button, it’s like it *tries* to start—the fan spins up for a second, but then everything just dies immediately. That's it.
Regarding those status lights on the motherboard, I noticed a tiny little LED that flickers on and off whenever I toggle the power switch on the back.
It’s just weird because it died so suddenly. The last time this happened, it just shut down and displayed "entering sleep mode" on the monitor, and once I rebooted, it worked fine. Now? I'm completely stumped.

Unplug the HDD, pull the GPU out, and give it another shot... maybe if you have a CD/DVD drive too.

I’ve tried pretty much everything I can think of, but I’m hitting a wall. There’s power going to the unit and the current seems fine, and most components seem to be functioning, but the second I try to actually boot it up, I get a short circuit somewhere and—poof—nothing. Just dead silence.
I’m probably just going to drop it off at a local repair shop and see what the techs say...
Is there any realistic way to make sure my files stay untouched? I'm really hoping I won't lose anything during the process.

The HDD should be fine if it didn't actually fry, but based on those symptoms... you probably just needed to mess around with the cables until you figured out what died.

William Richardson12 said:The HDD is probably fine if it didn't fry, but based on those symptoms, you should have just played around with the cables until you found the culprit.

What are you thinking, man? Based on that description, it’s either the power supply or the motherboard. If it were anything else, the motherboard would be throwing errors and hitting the internal speaker.

rowdybadger18 said:What’s your deal, man? Based on the description, it’s either the PSU or the motherboard. If it were anything else, the mobo would be throwing error codes through the onboard speaker.

or maybe a cable's fried, happened to me... you just bypass the components, strip the wires, and boom—it's like new again😉

But honestly, we can't just guess what died. You gotta do some actual manual diagnostics to get an answer.

If it were an issue with the HDD cable, the motherboard would be throwing errors again. Or at least spit out a message saying it can't find the boot partition. Though, I'll admit, your theory isn't entirely without merit.

I finally tracked down the culprit: the power supply bit the dust. Honestly, it’s a relief because it's a relatively easy fix. I'm just going to grab a new one, swap it out, and everything should be back to normal.
Thanks for the assist, everyone! 🎉

Let's just hope the PSU didn't take anything else down with it. 😉

It’s a good thing you caught the glitch early. Naturally, the first rule of troubleshooting would be checking the power supply unit to see if it's still functional. Unfortunately, my PSU fried a while back and took my graphics card right along with it 👎