Upgrading a PC: Replacing RAM, SSD and battery yourself

In short: An older computer often becomes snappy again with more memory, an SSD and a new battery; you clarify compatibility beforehand, back up data and work grounded and with the right tools.

In more detail: Upgrading is the cheapest way to extend lifetime. Important: first measure what slows it down (Task Manager: memory full? Disk at 100 %?), then replace specifically.

In Depth

What brings the most?

1. HDD → SSD: biggest gain on old computers (boot, programs, responsiveness).
2. Expand RAM (4 → 8/16 GB) if memory is permanently full.
3. Replace the battery on laptops with strongly declining runtime.
4. Clean and renew thermal paste if the computer gets hot and loud.
5. Renew the Wi-Fi card (on modular laptops).
6. Reinstalling/tidying software costs nothing and often helps immediately.

Checking compatibility

• Determine the model exactly (type plate, Win+R → msinfo32, manufacturer site, service manual/ifixit).
• RAM: type (DDR3/DDR4/DDR5; SO-DIMM for laptops), speed, maximum capacity, free slots; modules best identical in pairs.
• SSD: form factor (2.5-inch SATA, M.2 SATA or NVMe, key B/M, length 2280), controller support (boot from NVMe, older BIOS).
• Battery: original part or tested replacement, exact model number; no cheap batteries (fire risk).
• Connections and warranty: opening can affect warranty (see manufacturer; in the EU a right to repair is increasingly applicable).

Procedure and safety

1. Back up data; possibly an image of the old disk (Clonezilla, Macrium Reflect) and clone to the SSD.
2. Switch off the computer, pull the mains plug, on laptops disconnect the battery (if possible).
3. Ground yourself (touch a radiator/anti-static strap), clean surface.
4. Suitable tools (Phillips and Torx screwdrivers, plectrum), sort and remember screws.
5. Insert the module: mind the notch, firmly until it clicks.
6. Reassemble, start, check in BIOS/Task Manager; update drivers/firmware. Use no force; never damage or puncture lithium batteries.

When better not?

With soldered RAM/SSD (many thin laptops, MacBooks) upgrading is impossible or expensive. If the computer is very old (end of updates), upgrading often pays only if a Linux (light distro) makes continued operation safe. Weigh costs against a new device and second-hand purchase. If unsure, a repair café or a specialist workshop helps. Dispose of old parts properly (electronic waste, batteries).

See also: SSDs, DDR memory, Cooling and thermal paste, Task Manager and processes