You open Device Manager, find your graphics card sitting under Display adapters with a small yellow warning triangle, and the device status reads: Windows has stopped this device because it has reported problems (Code 43). It is one of the most frustrating GPU faults precisely because it tells you so little. Code 43 is not a single cause with a single fix. It is Windows throwing its hands up after the card reported that something is wrong, and that "something" could be a corrupt driver, a loose power cable, a card sitting half-seated in its slot, or silicon that is genuinely dying.
The good news is that most Code 43 cases are software, not hardware, and you can resolve them at home in an afternoon. The trick is to work through the causes in the right order: cheapest and most common first, hardware failure last. If you are also seeing the card vanish entirely rather than error out, our guide to a GPU that is not recognised covers that adjacent symptom, and our notes on fixing GPU driver crashes overlap heavily with the first fix below.
What Code 43 Actually Means
Code 43 is a generic Device Manager status, not a diagnosis. The card, or its driver, signalled a fault to Windows, and Windows disabled it to protect the system. Because the message is the same regardless of the underlying problem, you cannot read the cause from the error itself. You have to test for it. The realistic list of culprits, roughly in order of how often each one is to blame, is:
- Driver corruption — a bad, half-installed, or conflicting graphics driver. By far the most common cause.
- Power delivery — a loose PCIe power connector, or a PSU that cannot deliver enough clean power.
- Physical seating — the card not fully clicked into the PCIe slot, or a dirty slot.
- vBIOS or firmware — a corrupt or mismatched GPU BIOS. Rare and advanced.
- Failing hardware — a card that is genuinely dying, where Code 43 is the symptom of dead silicon.
Step One: A Clean Driver Reinstall
Because driver trouble causes most Code 43 errors, always start here. Do not simply reinstall over the top of the existing driver, because a half-broken installation will often survive that. Instead, do a proper clean removal:
- Download the latest driver for your exact card from NVIDIA or AMD directly, and save it before you start.
- Download Display Driver Uninstaller (DDU), boot into Safe Mode, and use it to completely strip out every trace of the existing GPU driver.
- Reboot and install the fresh driver you downloaded earlier, choosing a clean installation if the option appears.
One Nigerian-specific wrinkle: Windows Update will sometimes push its own generic GPU driver over your good one, reintroducing Code 43. If the error returns days after a clean reinstall, a Windows-pushed driver is the likely culprit. Our piece on a sensible driver update strategy explains how to keep Windows from overwriting a driver that was working perfectly well.
Step Two: Power and Connectors
If a clean driver reinstall does not clear the error, move to power. A modern GPU draws most of its current through dedicated PCIe power cables, and if one is loose, under-seated, or only partly clicked in, the card can report a fault that surfaces as Code 43. Power your machine down fully, open the case, and work through:
- Unplug and firmly reseat every PCIe power cable at both the GPU end and the PSU end, listening for the click.
- Avoid daisy-chained or split power connectors on high-draw cards; use separate cables from the PSU where you can.
- Consider whether your PSU is actually adequate for the card, especially if the error appears only under load such as in games.
Power quality matters more here in Nigeria than almost anywhere. NEPA instability, sudden surges when the grid returns, and the switch to and from generators all stress a PSU, and a unit that is ageing or marginal may fail to deliver steady power to the GPU. If you suspect the supply rather than the card, our guide on how to tell if your PSU is failing walks through the symptoms to check for before you spend money.
Step Three: Reseat the Card
With the case already open, reseating the graphics card itself is a quick and worthwhile test. A card that has shifted slightly in transit, or after being knocked, can lose proper contact in the PCIe slot and report Code 43. To reseat it cleanly:
- Release the slot retention clip, unscrew the bracket, and remove the card fully.
- Inspect the gold contact fingers and the slot for dust; a gentle clean of both helps, as dust and humidity build up quickly here.
- Press the card firmly back down until the retention clip clicks, then re-secure the bracket and reconnect power.
Step Four: vBIOS and Failing Hardware
If software, power, and seating have all been ruled out, the remaining causes are harder. A corrupt or mismatched vBIOS — the firmware on the card itself — can trigger Code 43, but reflashing it is an advanced procedure that can brick the card if done wrong, so it is best left to a technician unless you know exactly what you are doing.
And then there is the honest possibility: the card is dying. Code 43 is a known symptom of failing GPU silicon, particularly on older cards and on ex-mining cards that have run hot for years. If a card has been bought used and cheap, or has lived through repeated power surges, dead silicon is a real risk. Watch for these signs that the hardware itself is gone:
- Code 43 persists across a fully clean driver install, a different power cable, and a reseat.
- The error follows the card when you move it to another known-good machine.
- You also see artefacts, screen tearing, or crashes before the card drops out — our notes on GPU artefacts and screen tearing describe what dying silicon looks like on screen.
If the error follows the card into a second working PC, no software fix will save it. That card is failing.
Frequently Asked Questions
Is Error Code 43 always fixable? No, and it is important to be honest about that. When the cause is a driver, power, or seating problem, it is very fixable at home. When it is dying silicon — common on old or ex-mining cards — no amount of reinstalling will bring it back, and the only fix is a replacement card.
Can a bad power supply cause Code 43? Yes. A loose PCIe connector or a PSU that cannot deliver enough clean power will make the card report a fault that shows as Code 43, often only under load. Given how unstable NEPA power and generator switching are here, the PSU is always worth checking.
Will reinstalling Windows fix Code 43? Rarely worth it as a first move. A clean driver removal with DDU achieves the same software reset far faster. If a full reinstall still shows Code 43, the cause is almost certainly hardware — power, seating, or a failing card — not Windows.
The One Thing to Remember
Work the sequence in order: clean driver reinstall first, then power and connectors, then reseating, and only then suspect the hardware. Most Code 43 errors die at step one, and treating the cheapest, most common cause first saves you from wrongly condemning a card that simply had a corrupt driver — or from clinging to a card that is genuinely finished.
Not sure whether your card is worth saving or replacing? Build a fresh configuration to see what a reliable, surge-protected setup costs, or get in touch and we will help you diagnose whether your GPU is fixable or due for replacement.