RAM issues

Greetings, everyone. Please don't hold me to my word regarding whether this is strictly a RAM issue, but I suspect that might be the culprit based on my past experiences. On several occasions now, I have attempted to boot up my computer only to hear the fans spinning as if it were starting, yet nothing appears on the screen—just total darkness. I previously took the machine to a repair shop, and the technicians informed me that the RAM was over-utilized, which was preventing a successful boot sequence. Now, after more than a year, I am facing a similar situation; when I power it on, it takes an incredibly long time before anything finally displays on the monitor.
I should also mention that I am not particularly diligent about clearing out my drives, so I am currently sitting on a mountain of unnecessary programs and games that occupy a significant amount of space.
If the issue truly does stem from the memory, does anyone have advice on how to resolve this or free up enough resources to improve performance? Ideally, I would like to find a solution that prevents me from having to haul this thing back to a repair shop. I have already begun the process of deleting redundant software and games (though I am unsure if that even has any bearing on the matter), and I was wondering if I should perform a disk defragmentation. I attempted one recently, but the system ultimately notified me that certain files could not be defragmented.

Any and all advice would be greatly appreciated. 🙂

Maybe try running a memory test using MemTest86+...

Basically, you just grab the software from their site and burn it onto a blank CD—or, better yet, make a bootable USB drive. Then, just head into your BIOS settings and set it to boot from that drive to start the scan. Pretty straightforward, right?

If that doesn't turn up any errors, you might want to download CrystalDiskInfo. It’ll give you a clear look at your hard drive's health and let you know if everything is running smoothly or if there are some underlying issues you should worry about...

Is the monitor not turning on at all, or does it just take a while to kick in?
Are you hearing any beeps coming from the PC case?

I honestly don't get these repair techs who spout nonsense like "your RAM is too busy." That statement makes absolutely zero sense from a technical standpoint. Just run the MemTest like they suggested and you'll actually have some real data to work with, though you might not even need to go that far to find the culprit.

Memtest should tell you if the RAM is the culprit, but don't bother running it for just a few minutes—it’s notorious for passing the first round even when there's an issue. Best to just let it run overnight. I've had several instances where dust managed to settle right into the DIMM slots after using a can of compressed air, causing the whole system to hang on a black screen.

I appreciate the advice, everyone. It might just be some accumulated dust; I haven't performed a thorough inspection in quite some time.