How to disassemble an HP ProBook 4520s laptop: a complete guide with nuances

Laptop HP ProBook 4520s, released in 2010, still remains in demand among users due to its reliability and maintainability. However, over the years, even the most durable equipment requires maintenance: cleaning from dust, replacing thermal paste, or upgrading components. Disassembling this device has its own characteristics - from non-obvious latches to fragile cables that can be easily damaged if handled carelessly.

In this article you will find detailed step-by-step instructions with photographs of key stages, a list of necessary tools and list of common mistakesthat beginners admit. We will analyze not only the standard procedure for removing the back cover, but also the nuances of access to the motherboard, cooling system and battery. We will pay special attention unique keyboard mounting design in this model — its removal often causes difficulties even for experienced craftsmen.

Preparing for Disassembly: Tools and Precautions

Before you start disassembling HP ProBook 4520s, make sure you have everything you need. Missing even one tool can damage the housing or internal components. Here is the minimum set:

• 🔧 Phillips screwdriver (PH0 or PH1) - for most housing screws.
• 🔧 Plastic pick (or guitar pick) - for carefully prying the latches.
• 🧲 Magnetic mat or container - so as not to lose small screws (there are more than 20 of them here!).
• 🔍 Magnifying glass or flashlight — for inspection of small connectors and contacts.
• 🧴 Isopropyl alcohol (90%+) and a lint-free cloth for cleaning contacts.
• 🔌 Antistatic wrist strap (optional, but recommended when working with a motherboard).

Important: ProBook 4520s has aluminum elements in the body structure, which can be scratched if handled carelessly. Use the pick only in places where it is really necessary - do not try to pry it on metal parts!

⚠️ Attention: If your Recently laptop has been turned on, allow it to cool for at least 30 minutes. Capacitors on the motherboard can retain charge, which can be dangerous if accidentally shorted.

Removing the back cover: step-by-step instructions with photos

Let's start with the simplest thing - removing the bottom panel. IN HP ProBook 4520s it is secured with 11 screws, but their arrangement is asymmetrical, so remember or photograph the unscrewing process. Here is the sequence of actions:

1. Turn the laptop over and remove the battery (move the latch to the side UNLOCK).
2. Remove all screws marked in the photo below (3 short and 8 long). Please note: the screw under the battery is shorter than the others!
3. Gently pry the cover open with a pick, starting from the corner next to the optical drive. Here the latches are weaker.
4. Run the pick around the perimeter until the lid comes off completely. Don't use excessive force - if something doesn't work, check that all the screws are unscrewed.

Under the cover you will see the motherboard, cooling system, RAM slots and hard drive. In this model HDD is mounted in a metal slide, which are secured with four screws. To remove the drive, simply unscrew the screws and pull the tab.

⚠️ Attention: Do not touch the RAM contacts or connectors with your fingers - static electricity can damage the components. If you don't have an antistatic wrist strap, regularly touch the metal body of your laptop to drain the charge.

Access to the cooling system and replacement of thermal paste

Cooling system in ProBook 4520s - one of the most vulnerable places. Over time, the thermal paste dries out and the heatsink becomes clogged with dust, leading to overheating. To clean it and replace thermal paste, follow these steps:

1. Disconnect the fan and thermal sensor cables (they are marked white and red on the board).
2. Unscrew the 4 screws securing the heatsink (in the corners, in a criss-cross pattern so as not to deform the board).
3. Remove the heatsink and clean it of old thermal paste with isopropyl alcohol. For hard-to-reach places, use cotton swabs.
4. Apply new thermal paste (we recommend Arctic MX-4 or Noctua NT-H1) a thin layer on the processor and chipset. Layer thickness - no more than 0.5 mm!

Component	Recommended thermal paste	Amount (mg)
Central Processing Unit (CPU)	Arctic MX-4	80–100
Graphics chip (GPU)	Noctua NT-H1	60–80
Chipset (Northbridge)	Thermal Grizzly Kryonaut	40–50

After replacing the thermal paste, reassemble the cooling system in reverse order. Make sure the fan rotates freely - sometimes dust accumulates on the shaft, causing it to jam. If the blades cling to the body, clean off the deposits with alcohol.

Removing the keyboard: hidden latches and common mistakes

Keyboard in HP ProBook 4520s It is attached not only with screws, but also with plastic latches that are easy to break. Here's how to remove it without damaging it:

1. Remove the 3 screws under the battery (they are marked with a keyboard icon).
2. Gently pry the keyboard with a pick, starting with top right corner (here the latch is weaker).
3. Lift the keyboard and disconnect the cable by pulling the black tab of the connector (not the wires!).

Mistakes that are often made when removing the keyboard:

• ❌ They try to remove it from the left corner - there the latch is the strongest, which leads to breakage.
• ❌ They pull on the cable instead of the connector tongue - this damages the contacts.
• ❌ If all 3 screws are not unscrewed, the keyboard “does not give in” and is broken by force.

What to do if the latch is broken?

If the plastic keyboard latch is cracked, it can be temporarily fixed with hot glue (for example, Bison Poly Max). However, for reliability, it is recommended to replace the entire top panel (part number: 6050A2469001 for backlit model).

Replacing RAM and hard drive

HP ProBook 4520s supports up to 16 GB RAM (2 DDR3-1333 MHz slots) and standard 2.5" HDD/SSD. For upgrade:

1. RAM: Press the latches on the sides of the module and remove it. Insert new strips until they click (the corner with the notch should coincide with the key in the slot).
2. HDD/SSD: Unscrew the 4 screws on the metal slide, slide the drive to the side and lift it by the tab. SSD may require adapter 2.5"→9.5 mm.

Compatible RAM Models:

• 🔹 Kingston KVR1333D3S9/8G (8 GB, 1333 MHz, CL9).
• 🔹 Crucial CT102464BF1339 (8 GB, 1333 MHz, low profile).
• 🔹 Samsung M471B1G73DB0-YK0 (8 GB, original module for HP).

⚠️ Attention: When installing two RAM modules, use sticks of the same size and frequency. Otherwise, the laptop may not boot or work in single-channel mode.

Cleaning the cooler and replacing thermal pads

Fan in ProBook 4520s often becomes clogged with dust, which leads to noise and overheating. To clean it:

1. Remove the radiator (as described above).
2. Unscrew the 2 screws securing the fan and disconnect its cable.
3. Blow the blades with compressed air or wash them in warm soapy water (after they are completely dry!).
4. Lubricate the fan shaft with 1 drop silicone grease (For example, WD-40 Specialist).

Thermal pads (on memory chips and bridges) lose their elasticity over time. Their replacement is required if:

• 🔥 Video card temperature exceeds 90°C under load.
• 🔥 The pads have become fragile or crumble when touched.
• 🔥 They show cracks or signs of drying.

Recommended gaskets:

• 🟦 Arctic Thermal Pad (1 mm) - for memory chips.
• 🟦 Fujipoly Ultra Extreme (1.5 mm) - for bridges.

Assembling a laptop: checking and testing

Once completed, reassemble the laptop in reverse order, following these tips:

1. Make sure that all cables are connected tightly (especially the keyboard and touchpad).
2. Tighten the screws in a crisscross pattern to prevent the case from twisting.
3. Before turning on, check if there are any foreign objects left inside (screws, pick).

After assembly:

1. Turn on your laptop and check the temperature HWMonitor or AIDA64.
2. Test the keyboard (all keys should respond without delay).
3. Make sure the fan turns on under load (run Prime95 for 5 minutes).

If the laptop does not turn on:

• ⚡ Check the connections of the battery and power supply.
• ⚡ Make sure the RAM is installed correctly (try one stick).
• ⚡ Inspect the motherboard for foreign objects or short circuits.

Frequently asked questions (FAQ)

Is it possible to replace the processor in HP ProBook 4520s?

Yes, but with restrictions. The laptop supports family processors First generation Intel Core i3/i5/i7 (Socket G1). The maximum possible upgrade is Core i7-640M (2.8 GHz, 4 cores). However, installing it may require a BIOS update (version F.61 or newer).

How to remove the screen to replace the matrix or hinges?

To do this you need:

1. Remove the front frame of the screen (it is held on by latches; pry it with a plastic pick).
2. Unscrew the 4 screws securing the hinges to the body.
3. Carefully disconnect the cable from the matrix and webcam.

Recommended matrix replacement - LP156WH2-TLQ1 (15.6", 1366×768, glossy).

What should I do if the touchpad does not work after assembly?

The problem is usually an unconnected cable. Unscrew the back cover and check:

• Is the touchpad connector connected to the motherboard (it is located next to the RAM slots).
• Is the cable pinched by the case (sometimes the screws put pressure on it).
• Is the touchpad enabled in the BIOS (Advanced → Device Options → TouchPad).

Which SSD is better to install to speed up work?

Recommended models:

• Samsung 870 EVO (500 GB–1 TB, SATA III) - the best choice in terms of price/quality.
• Crucial MX500 (1 TB) - reliable and energy efficient.
• WD Blue SA510 (500 GB) - a budget option with good speed.

After installing the SSD, clone the system from the HDD using Macrium Reflect or Clonezilla.

Why does my laptop turn off when unplugged, even if the battery is charged?

Probable reasons:

• The battery is faulty (check its capacity in HP Support Assistant).
• The contacts on the power connector have oxidized (clean them with alcohol).
• The power controller is malfunctioning (diagnostics of the motherboard is required).

If the battery is swollen, replace it immediately - it's dangerous!