notebook-hardware-guide

before you open it

• Get the service manual first. Dell, HP and Lenovo publish one for every business model: search for the model name plus "service manual" or "hardware maintenance manual". It shows every screw and every clip.
• Shut down completely. Sleep is not off, and with fast startup neither is Shut down: hold Shift while you click it, or use Restart and switch off when the logo appears.
• Unplug the charger. Once the cover is off, disconnect the battery cable before anything else. Some models have a setting in the BIOS that switches the internal battery off for service.
• Screws have different lengths. Tape each one to a sketch of the underside in the place it came from.
• Look for hidden screws under rubber feet and stickers before you pry.
• Use a plastic pick, start at a corner near the hinges or at the ports, and work round. If a spot does not give, there is a screw left.

what is inside, and what can be replaced

• Business models usually let you replace the battery, the SSD, the Wi-Fi card and at least one memory module.
• Thin consumer models often have everything soldered except the SSD, and sometimes that too. Find out before you promise an upgrade.
• The fan and the heat pipe come off as one piece. Taking them off means new thermal paste.

it is dead: do the power drain first

A notebook that does nothing at all, or shows a light but no picture, is often not broken. The small controller that manages power has hung, and it never loses power as long as a battery is connected.

1. Unplug the charger and everything else.
2. If the battery comes out without tools, take it out.
3. Hold the power button down for 30 seconds.
4. Connect the charger only, and switch on.

Models with a sealed battery often have a pinhole on the underside for the same purpose: press it with a paper clip for ten seconds. This fixes a surprising share of "dead" notebooks, and it costs one minute.

chargers and USB-C

• The charger must deliver at least the wattage printed on the original. A weaker one charges slowly, or not at all while the notebook is working, and many models then slow the processor down. "Slow since last week" can be a borrowed charger.
• With USB-C the cable counts as well. Above 60 W it needs to be rated for 5 A. A thin phone cable limits the power, whatever the charger can do.
• A dock passes on less than its own power supply delivers. Check the wattage the dock gives to the notebook, not the one on its power brick.
• Chargers with a round plug from Dell and HP have a thin pin in the centre that tells the notebook what the charger is. When that pin or its wire breaks, the notebook runs but does not charge, reports an unknown adapter at start, and runs slowly.
• Test with a known good original charger before you suspect the battery or the board.

battery health

• Compare the full charge capacity with the design capacity. Below about two thirds, the battery is worn and worth replacing.
• A notebook that lives on a dock ages its battery by sitting at 100%. Most vendors have a setting, in the BIOS or their tool, that stops charging at 80%.
• A battery that swells is a fire hazard. The signs: the touchpad no longer clicks, the case bulges, the lid no longer closes flat, the notebook rocks on the table. Stop using and charging it, do not press on it or pierce it, and take it to a collection point.

# Windows: writes a report with capacity and history
powercfg /batteryreport /output "%USERPROFILE%\battery.html"

# Linux
upower -i $(upower -e | grep BAT)

# macOS
system_profiler SPPowerDataType

memory and SSD upgrades

• Check what the machine takes before you buy: the memory generation (DDR4 and DDR5 do not fit each other), the highest supported size, and the length of the SSD slot.
• For the SSD: put the new one into a USB enclosure, clone the old drive onto it, then swap. That way the old drive stays untouched as a fallback.
• Suspend BitLocker before the swap or have the recovery key at hand.
• Memory goes in at an angle and is then pressed flat until the two side clips catch.
• After closing the cover, check in the BIOS that everything is seen before you start the operating system.

ribbon cables and their latches

• Keyboard, touchpad, display and fingerprint reader hang on flat ribbon cables in latched connectors. Pulling a cable out of a closed latch tears the connector off the board.
• Look closely before touching: either a small bar flips up, or a frame slides out a millimetre. Open it with a fingernail or a plastic tool.
• Putting it back: slide the cable in straight up to the printed line, then close the latch. A keyboard where some rows of keys do nothing after a repair has a cable that sits crooked.

display faults: panel, cable or graphics

• Connect an external monitor. A good picture there means the graphics chip is fine and the fault is in the panel or its cable.
• Shine a torch at the dark screen at an angle. If you can faintly see the desktop, the panel works and its backlight does not.
• Lines or flicker that change when you move the lid: the cable through the hinge.
• Lines that stay exactly the same whatever you do: the panel.
• A picture in the BIOS but not in Windows: a driver, not hardware.
• Before any of that, press the brightness keys and the key that switches between displays. It happens.

liquid on the keyboard

1. Switch it off at once: hold the power button until it is dark. Do not save, do not shut down nicely.
2. Unplug the charger and everything else. If you can, open it and disconnect the battery.
3. Open the lid wide and stand the notebook like a tent, keyboard down, on a towel.
4. Leave it for at least two days. No hair dryer, no rice: one bakes it, the other does nothing.
5. Water that was caught early often leaves no damage. Anything with sugar or milk dries into a sticky, corrosive film and needs to be opened and cleaned with isopropyl alcohol before it is switched on again.

The damage comes from current flowing through wet parts, not from the liquid itself. Every second it stays on counts.

heat and fan noise

• The usual cause is a mat of lint between the fan and the cooling fins, like felt. Blowing into the vents from outside only moves it around. Open the cover, hold the fan still, and pull the mat out.
• New thermal paste after four or five years brings a hot notebook back to normal.
• On a bed or a blanket the intake underneath is closed. That alone makes a notebook hot and slow.
• A fan that runs for no reason: check for a BIOS update. Vendors fix fan behaviour that way more often than you would think.
• Is it slow because it is hot? The Windows PC is slow, step 6.

keyboard and touchpad

• To separate hardware from software, test in the BIOS setup or with a live Linux stick. A key that fails there is a hardware fault.
• A single key cap and its little scissor hinge can be replaced. A whole keyboard is often riveted into the upper case and comes as one part with it.
• A touchpad that stopped working: look for the function key that switches it off, then for a swollen battery underneath it.

after the repair

• Weak Wi-Fi after a repair: one of the two tiny antenna plugs on the Wi-Fi card came off or was pinched.
• No sound, no camera, a dead port: a ribbon cable that was not put back.
• A screw left over means something is not fastened. Do not ignore it.

getting into the BIOS and the boot menu

From a running Windows you do not need the key at all: hold Shift and choose Restart, then Troubleshoot, Advanced options, UEFI Firmware Settings. Or from an elevated prompt:

shutdown /r /fw /t 0