HP LaserJet Pro black screen issue

I was sitting there when these weird gray lines suddenly streaked across my screen, so I did what any panicked person would do and just killed the power. Now, whenever I try to boot it back up, the cooling fans kick into gear, but the screen stays pitch black—just total nothingness. I see that little LED that usually indicates CPU load flicker on for a split second and then die right along with it.

What should my next move be? I’ve already tried reseating the RAM, pulling it out and clicking it back in, but it hasn't made a lick of difference.
How can I actually pinpoint where the breakdown is happening?

Brandon Chavez9 said:Gray lines popped up on my screen and I shut it down immediately. Now when I turn it back on, the fan spins up, but the screen stays totally black—nothing happens at all. That little light—the one I think indicates CPU load—flickers on for a second and then just dies.

What should I do? I already tried reseating the RAM, but no luck there.
How can I figure out what actually broke?

Is there any chance you could try plugging it into an external monitor? If you hook it up and still get no picture, it’s highly likely your graphics card or the motherboard has bit the dust. You'll probably need to take it to a repair shop, because on most laptops—if it's the GPU—it's soldered right onto the motherboard. They'd have to desolder it and solder a new one on, and honestly, I'm not sure if that's worth the cost. And if the whole motherboard is fried, well, you're looking at buying a new board plus the labor... Looking at your specs, this isn't exactly a powerhouse, and it's been around for a few years now. Just being real with you—for $667, you could probably pick up a much faster machine than what you're running right now. My two cents? If it really is the component I suspect, it might just be better to let it go rather than sinking so much cash into a repair.

I had a similar issue once where both my GPU and motherboard went south at the same time on my PC
The screen just stayed black, so I sent it off to the repair shop since it was still under warranty
They checked everything—the graphics card, the power supply, the RAM, and the motherboard. At first, they actually suspected the GPU, but when they swapped it out with a different one, the problem persisted
Then they finally moved on to the motherboard, and as soon as they popped a new one in, the whole computer roared back to life

It’s probably looking that way, but honestly, after eight solid years of service, that machine definitely earned its keep and paid for itself many times over!