Hi! If your computer screen shows strange colors, we can approach it calmly and figure out whether it’s a Windows setting, a cable/signal issue, or the monitor itself. I’ll stick to safe checks (nothing scary, no “tweaks” you can’t undo).

First, what kind of “strange” are we talking about?
• A warm yellow/orange tint like everything looks sepia
• A green/pink/purple cast, like one color channel is missing
• Inverted colors (light looks dark, odd neon look)
• Washed-out / faded colors (especially in photos/video)
• Over-saturated or “too vivid” colors that don’t look natural

And is this happening on a laptop screen, an external monitor, or both?

That’s a helpful description. When the desktop itself looks off, it can be one of these “simple explanation” categories:

1) Windows color features — Night light (warm tint), Color filters (can make everything look odd), or HDR (sometimes makes colors look washed-out or too intense depending on the monitor).
2) Monitor settings — the monitor’s own menu might be on a mode like “Vivid,” “Game,” “Movie,” or an unusual color temperature.
3) Signal/cable — a slightly loose HDMI/DisplayPort connection can cause strange tinting (like a missing color channel).
4) Graphics output behavior — after an update, the display driver can behave differently, especially with video playback.

Two quick questions (pick whichever is easiest to answer):
• Did this start after a Windows update or graphics update, or did it just “appear” one day?
• Does the monitor show the wrong colors even in its own built-in menu (the monitor OSD), or only in Windows?

If the monitor’s own menu looks mostly normal, that often suggests the panel itself is okay and we’re looking at either Windows settings or the signal coming in. The fact that it’s more obvious in photos/video is also interesting because video playback can trigger things like HDR and different rendering paths.

Since your dad is the one using it, I like to start with “non-technical” checks that are easy to explain on the phone:

A) Ask him to open Windows Settings and search for “Night light” — if it’s on, colors can look warmer or slightly strange.
B) Search for “Color filters” — if a filter is enabled (sometimes by accident), it can make everything look tinted or high-contrast.
C) Search “HDR” in Display settings — HDR being on with a non-HDR monitor can make things look faded or overly intense.

Before he changes anything, can you tell me: is it more like a warm yellow look, or more like a green/pink cast?

That “shift when video starts, then settle” can happen with HDR switching on/off, or with video color enhancements. A cable issue can also cause odd color tinting, but it’s usually more constant (like “everything is purple” because a color channel is missing). What you’re describing sounds more like a mode change triggered by video.

A safe way to separate “Windows/video mode” from “hardware path” is this question:

Does a screenshot look normal?
If you take a screenshot and view it on another device (phone), does the screenshot look normal? If yes, it suggests the computer is creating the image correctly and the oddness is happening in the display chain (monitor/cable/settings). If the screenshot also looks weird on your phone, it points more toward Windows settings or color profiles.

If screenshots are too complicated for him, we can do an even easier test: does the problem show up on the Windows sign-in screen, or mainly after he’s logged in and using apps?

Yep — monitor picture modes can make reds look “too hot” and skin tones odd, especially “Vivid/Game” presets. Sometimes a power blip or an accidental button press can switch modes, and it can feel like it “suddenly happened.”

Since the sign-in screen is mostly okay and it’s stronger in browsers/video, I’d keep two “most likely” tracks open:

Track 1: Monitor picture preset (Game/Vivid/Dynamic Contrast / unusual color temperature).
Track 2: Windows video/color features (HDR, night light, color filters, or a driver/app color pipeline change after updates).

Here’s a low-stress question you can ask him that doesn’t feel technical:
“Can you open a plain white page (like a blank Notepad or a simple website) — does white look truly white, or does it look tinted?”

Also: is he using any adapters (HDMI-to-DisplayPort, docks, splitters), or is it a straight HDMI cable from the PC to the monitor?

That concern is very common (and totally reasonable). The good news is we can diagnose without “getting lost” in menus.

Two safe, reversible checks that usually don’t trap anyone:

1) Cable reseat (no settings)
If you can be there in person, unplug/replug the HDMI at both ends firmly. If a connector is slightly oxidized or not fully seated, reseating can change color behavior. No software changes involved.

2) Confirm Windows isn’t applying a filter
In Windows Settings, quickly confirm Color filters are off and Night light is off (for a test). These can make colors look “wrong” even though nothing is broken.

If you remote in later, another useful clue is to check whether HDR is enabled in Display settings. HDR can make colors look washed-out or over-saturated depending on the screen and content.

One more question that helps: does your dad remember seeing any quick keyboard shortcuts or “ease of access” changes recently? Color filters can sometimes be toggled by accident.

Windows updates can change defaults or re-detect display capabilities, so it’s possible a display feature got enabled or behaves differently even if your dad didn’t touch anything. That’s why I like to confirm the “simple” stuff first.

As for a failing graphics card: it’s on the list, but it’s not the first conclusion from what you described. When a GPU is failing, you often see additional symptoms like random crashes, heavy artifacts (blocks/lines), problems even at the sign-in screen, or issues on multiple displays consistently. You’re describing something more “mode/processing” related (especially with video starting).

When you visit, the cleanest diagnostic plan (no deep fixes) is:
• Observe whether the monitor’s own menu looks normal.
• Reseat the HDMI and, if possible, try a different HDMI cable for a few minutes.
• Check Windows for Color filters, Night light, and whether HDR is enabled.
• Note whether the odd color is system-wide or mostly in the browser/video.

If you want, tell me what you find in those checks and we’ll narrow it down logically without guessing.