Hey! We can troubleshoot a computer fan not spinning without doing anything risky. First, I want to clarify which fan we’re talking about, because the logic changes a lot:
• CPU fan not spinning (on the heatsink) is the most urgent — it can cause thermal throttling or shutdowns.
• Case fan not spinning affects airflow, but the PC may still boot normally for a while.
• GPU fans not spinning can be totally normal at idle due to “zero RPM mode” on many graphics cards.
• Laptop fan not running can be tricky because some models stay quiet until a temperature threshold is reached.

A few quick questions (answer what you can):
1) Desktop PC or laptop? If desktop: do you mean the fan on the CPU cooler, the front/rear case fans, or the graphics card fans?
2) When did it start — after a Windows update, BIOS update, cleaning, moving the PC, or a new build/upgrade?
3) Any symptoms like overheating, random shutdowns, “CPU fan error” at boot, burning smell, or loud fans that suddenly stop?

Thanks — since it’s the CPU fan stopped spinning and it began right after moving the tower, my first suspicion is something simple like a loose connection, a fan hub/splitter issue, or the fan cable being pulled slightly out of the CPU_FAN header on the motherboard.

Let’s do safe checks (no downloads, no “tweaks” that trap you):
1) When you press the power button, does the CPU fan spin for even a second during startup? Some boards briefly spin fans at boot, then follow a fan curve.
2) Do any other fans spin (rear case fan, front fans, GPU fans)? This helps separate “fan power” from “one fan/header.”
3) If you’re comfortable: with the PC fully off and power cable unplugged, can you visually confirm the CPU fan cable is plugged into the motherboard header labeled CPU_FAN (not CHA_FAN or AIO_PUMP)? Just look — don’t force anything.

Also: do you see the CPU fan RPM anywhere (BIOS/UEFI hardware monitor or a motherboard utility), or does it read 0 RPM?

That’s really helpful. If the CPU fan shows 0 RPM in BIOS and never spins at power-on, this is likely not a Windows/fan-control-software issue. It points to a physical connection, a bad fan, or (less commonly) a problem with the CPU_FAN header.

Before anything else: if the CPU fan truly isn’t spinning, I’d avoid running the PC for long — overheating can trigger throttling or a thermal shutdown, and it’s not worth stressing the CPU.

Here’s a simple, low-risk diagnostic path that doesn’t “fix” anything permanently — it just tells us what’s wrong:
• Check the obvious: make sure the fan blades aren’t blocked by a cable tie, wire, or the edge of the fan shroud (it happens after moving a tower).
• Check the plug seating: the 3-pin/4-pin fan connector should sit straight and fully on the header (it usually has a little guide rail).
• Identify the fan type: is it a 4-wire PWM fan or 3-wire DC fan? (You can count wires on the connector.) Some boards have a BIOS setting to treat a header as PWM vs DC — but we won’t change that yet; we’ll just note it.

Quick question: is your CPU cooler connected directly to the motherboard, or through a fan hub/splitter?

Totally fair — you don’t have to start unplugging random stuff. We can keep this “safe and simple” and still learn a lot.

Since it’s a 4-wire fan and BIOS shows 0 RPM, the two most common “simple fix” outcomes are: (a) the connector is almost on but not fully seated after the move, or (b) the fan motor isn’t starting (bearings/age), even though it spins freely by hand.

Here are two checks that are still gentle: 1) In BIOS/UEFI hardware monitor (or “Q-Fan / Fan Control” depending on board), do you see any warning like “CPU fan not detected,” or is it just 0 RPM? Some boards also show CPU temperature right there — if the CPU temp climbs fast while the fan stays 0, that confirms it’s truly not starting.
2) With the side panel on or off, does the PC ever do an emergency ramp (other fans blasting) and then slow down again? That can happen when the CPU is heating and the system is trying to compensate.

Also, because you mentioned moving desks: did you change where the PC sits (like tighter corner, carpet, against a wall)? Reduced airflow can make symptoms show up faster, even if it didn’t “cause” the fan issue.

Great question — some motherboards do allow “fan stop” on certain headers, and GPUs commonly do zero RPM mode at idle. But for the CPU_FAN header, full fan-stop is less common (and many boards deliberately avoid it for safety).

The key detail is: you saw CPU temps climb quickly in BIOS while CPU fan RPM stayed 0. BIOS is “below Windows,” so software isn’t controlling things yet — that strongly suggests the fan isn’t being powered/spun when it should.

At this point, the safest diagnostic logic is:
• If the fan never spins at boot and reads 0 RPM in BIOS: focus on the connection (seating/placement), then the fan itself, then the header.

If you’re willing to do exactly one simple physical check (still safe): with power unplugged, gently press the fan connector straight down to confirm it’s fully seated on the CPU_FAN pins. No yanking, no forcing — just a “firm-but-gentle” seat check. That alone resolves a surprising number of “CPU fan not spinning after moving PC” cases.

If that doesn’t change anything, the next step is usually a quick “is it the fan or the header?” test — but I’ll only describe the logic, not push you into doing it if you’re not comfortable.

You’re thinking about it the right way. A desktop with a non-spinning CPU fan often won’t “instantly die,” but it can throttle hard (slow down), throw a temperature warning, or do a protective shutdown if temps get too high. That’s why your choice to power off in BIOS when temps rose was perfect.

For distinguishing “fan curve behavior” vs real failure, the easiest (and safest) indicator is exactly what you already checked: BIOS hardware monitor + rising CPU temperature + 0 RPM. A normal fan curve still shows some RPM when the CPU warms up. If it stays 0 while the CPU heats quickly, it behaves like a detection/power issue, not a normal curve.

If you want a simple, non-invasive checklist for next steps (without doing the full repair):
• Confirm airflow: give the tower breathing room (tight under-desk spaces can accelerate overheating symptoms).
• Confirm the connector: CPU fan plugged to CPU_FAN, seated straight, cable not under tension.
• Confirm behavior: does the fan ever twitch/spin during power-on? If it never even twitches, that leans toward power/connection or a failed fan motor.
• Confirm readings: BIOS shows 0 RPM and CPU temp climbs quickly.

With those facts, you can decide whether to stop at diagnostics (safe) or hand it off to someone comfortable with hardware testing. Either way, you’ll be walking in with clear evidence instead of guesswork.