HP — 3 long, 4 short beeps

The most-googled HP beep code, and a deceiving one. The BIOS is reporting a graphics subsystem failure, but the underlying cause is almost always thermal — and almost always fixable for the cost of a £4 tube of thermal paste.

What the beep code means

HP's BIOS uses three long beeps then four short beeps to report graphics controller / video subsystem failure. The BIOS tried to initialise the GPU, did not get a response, and stopped — that is why your screen stays black.

On HP all-in-ones and most Pavilion desktops, the GPU is integrated into the motherboard. So "graphics failure" really means "the part of the motherboard that handles graphics has stopped responding". The fix depends on whether the chip is dead or just thermally compromised.

The fast diagnosis: dead or thermal?

Touch the back of the case (or the underside of a laptop) where the GPU sits. If it has been on for more than two minutes:

Hot, almost too hot to keep your hand on it → the GPU is alive but overheating. The thermal fix below has a high chance of working.
Mildly warm or cool → the GPU is not getting power, or has died entirely. The thermal fix is unlikely to help; you are looking at motherboard-level failure.

The thermal repair (works for ~40% of cases)

What you need

Phillips screwdriver (PH1 for laptop screws, PH2 for desktop)
Isopropyl alcohol 90%+ (or pure)
Lint-free cloth or coffee filter
Thermal paste — Arctic MX-4 (£5), Noctua NT-H1, or any modern paste. Avoid anything from the "value" end of Amazon.
A vacuum cleaner with a brush attachment, or a can of compressed air
About 45 minutes

The procedure

Unplug everything. Hold the power button for 30 seconds to drain capacitors.
All-in-one: lay it face-down on a soft surface (a folded towel works). Remove the back cover screws — usually 4-6 around the edge plus a hidden one under the stand.
Pavilion desktop: remove the side panel.
Laptop: remove the bottom case screws — there are usually 8-12, including some under the rubber feet.
Locate the heatsink — it is the large metal slab with copper pipes leading to a fan. Photograph the cable layout before unplugging anything.
Vacuum out the dust. The fans and the radiator fins are likely packed solid with grey felt — that is years of compressed dust and is the actual reason your machine is overheating.
Undo the heatsink screws in reverse numerical order (the screws are labelled 1, 2, 3, 4 — undo 4 first, then 3, etc., to avoid bending the chip).
Lift the heatsink gently. If it sticks, twist slightly — do not pry.
Wipe the old paste off the GPU and CPU dies (and off the heatsink contact patches) with isopropyl alcohol and the lint-free cloth.
Apply a pea-sized blob of fresh paste to the centre of each chip die. Do not spread it — the heatsink pressure does that for you.
Refit the heatsink, screws in numerical order (1 first, then 2, etc.) tightening each one a quarter-turn at a time so pressure stays even.
Reassemble, plug in, power on. If you hear the normal POST single beep (or no beep) and see the BIOS or Windows screen, you have fixed it.

If the thermal fix did not work

Two more things worth trying before giving up:

Reseat the RAM. Sometimes a RAM contact issue throws the wrong beep code. Pull each stick, blow on the contacts, push back in firmly.
CMOS reset. Find the CR2032 battery on the motherboard, remove for 60 seconds, replace.

If neither helps, the integrated GPU is genuinely dead. Options:

Motherboard replacement. Available on eBay for most HP all-in-ones at £80-150. Worth it only if the rest of the machine is in good shape.
External GPU bypass. On some Pavilion desktops you can plug a discrete graphics card into a PCIe slot, disable the integrated GPU in BIOS (if you can get to the BIOS — which you cannot if the integrated GPU is dead). Often impossible in practice.
Reflow / reball. Some repair shops can re-solder a failing GPU chip. £80-150 if you can find someone who does it. Usually a temporary fix that lasts 3-12 months.
Replace the machine. If it is more than 5 years old, this is normally the right call.

How to prevent it next time

If you fix this and want to avoid it happening again on your next machine:

Vacuum the rear vents and fan grilles every six months. Five minutes, prevents 80% of thermal failures.
Avoid placing all-in-ones flush against a wall. They vent out the back.
If the fan gets loud or runs constantly, that is the early warning. Clean it then, before the chip cooks.

Frequently asked

What does 3 long beeps and 4 short beeps mean on an HP? +

Three long beeps followed by four short beeps is HP's code for a graphics controller or video subsystem failure. On HP all-in-ones (Pavilion, EliteOne) and many Pavilion desktops, this is almost always the integrated GPU on the motherboard failing — most often because the heatsink has clogged with dust and the chip has been thermally stressed for too long. Clean the heatsink and reapply thermal paste before assuming the motherboard needs replacing.

My HP all-in-one beeps 3 long 4 short and the screen stays black. Can I fix it without a new motherboard? +

Often, yes. The fix that works most often: open the back cover, vacuum out all the dust around the heatsink and fan, remove the heatsink, clean off the old thermal paste from the GPU and CPU, apply fresh paste (Arctic MX-4 or similar), reassemble. This brings about 4 in 10 affected machines back to life. If it works, the BIOS will stop beeping and the display will come on.

Does 3 long 4 short ever mean RAM? +

No. RAM failures on HP are usually 1 long, 3 short or 3 long, 3 short. Do not waste time pulling the RAM — the 3 long, 4 short pattern is specifically the video subsystem.

Why is this so common on HP machines specifically? +

Two reasons. First, HP used the same all-in-one motherboard design across millions of Pavilion units from 2017-2020, with a known thermal weakness in the integrated GPU. Second, the all-in-one form factor traps dust against the rear vents, so heatsinks clog faster than in a standard tower. The combination is why this specific beep code is googled tens of thousands of times a month.