Screen is working, but has a blue "Out Of Range" box bouncing around it?

Hello everyone, I'm pretty new here but needed some advice regarding a new computer and a rather... odd error I can't seem to find any information on. I've searched all through google, various forum posts, but can't seem to find anything relating to this exact issue. This place by far seemed to be the most helpful, so I'm hoping that someone here may know how to figure out the problem and fix it, if possible.

Okay so, here's the problem:
I have a new PC, built it myself, less than three months old. Never had much trouble with it until about three days ago, when in the middle of browsing the internet, the screen went black for a second, then came back with a blue "Out Of Range" box that then proceeded to bounce around the screen. The screen itself is still working, I can see what I'm typing and can interact with things still... but with this ever-present blue box bouncing around and getting in the way.

I've scoured the internet for solutions, but could never find a situation quite like mine. Where the screen still worked despite supposedly being "out of range". Still, I tried every method I could -- from changing the resolution, to trying safe mode, to turning it on using "low resolution video" mode. Only the last one worked, and it only worked twice before no longer doing so. It started today as soon as I powered on the PC, before it even got to the loading symbol for the BIOS or Windows 10 itself. And nothing I've tried till make it go away.

I think it may be my monitor, but I'm not sure? It's pretty a pretty old Duracom flat screen, and I had to use a VGA to HDMI converter for it to work at all (which may also be an issue?). It's given me a few problems before (turning itself off, messing up it's own resolution, etc), though this one is definitely new. I unfortunately don't have a second monitor to test the problem with. Mainly I'm here to see if anyone knows if it may be caused by something else (like my GPU) before I try to save up for a new monitor. It'd suck to go out and buy an expensive new monitor only to find out that it wasn't the problem, haha...

Here's my specs, if they help:
OS: Windows 10
GPU: Gigabyte GTX 1060 6GB
CPU: Coffee Lake Intel Core i3-8350K
HDD: 1TB Seagate BarraCuda (ST1000DM010)
Motherboard: GIGABYTE Z370 HD3P (rev. 1.0)

Any help would be appreciated in figuring this out, I've barely had this PC for over a month and it's pretty disheartening to have it already be giving me problems. Especially since it's also how I work and keep in contact with friends and family. The problem was also so out of the blue, it'd been working great for the most part until that day. And now suddenly it's nearly impossible to get anything done because there's a moving box blocking part of my screen in various places at all times. :(

Cycloid Torus

Posts: 4,842   +1,662
"Out of Range" bouncing box, but screen still has information (not blacked out). Video subsystem is GTX1060 (new - sending signal as HDMI), video cable (HDMI), adapter (HDMI to VGA), older monitor (Duracom - receiving signal as VGA). 1060 card offers many more options than the monitor knows how to handle. The adapter takes a digital signal and has to change this into an analog signal.

First, power down everything and reconnect ALL connectors in video subsystem (including power to card while you are at it.) Fixed?

If not: Can you confirm setting of 1060 to 60 Hz refresh rate and 800x600 resolution? Fixed?

If not: Can you remove video driver entirely (using DDU -- see downloads) and reboot using the Windows standard driver. Fixed?

If not: Need specifics on hardware in your video subsystem. Be aware that some adapters only work in one direction, others may suffer 'infantile' failure. Check manual on monitor to determine what limits you face.

As to monitors, many good LED monitors are coming off lease. I bought several from well established high-rep vendors on eBay. You will be pleased with what a 1060 can do with a pure HDMI connection.
Thank you for the reply, I tried everything above that was suggested, and I think I may have found that the monitor is indeed the problem...

Confirmed the resolution, changed it to a lower one, and double checked it was on 60hz, no visible change.

Removed drivers using DDU and rebooted, no visible change.

Powered down everything and reconnected it all, no visible change... however, while doing this I decided to go ahead and remove the graphics card entirely and power on using only the motherboard and the monitor without the VGA - HDMI adapter to see if it was causing the problem of being one way, as you suggested. I found that, even without the adapter and use of the graphics card, the issue was still present. So that has ruled out it being both the card and the adapter.

Which means it must be my monitor. Unfortunately, I can't fiddle with the settings on it, since as long as the computer is on and the "out of range" shows, I can't get the buttons to work. So I think it's simply reached it's last legs and I'm going to have to get a new one...

Thank you again for your help and quick response!