You can Run System Checks- sfc /scannow in Command Prompt (Admin) – scans for system file issues. chkdsk /f – checks disk errors. Use HP Diagnostics (press F2 at boot) to test memory and hardware.

It sounds like there may be a driver or hardware detection problem causing your laptop to not recognize the touchscreen hardware. Windows might not even recognize a "HID-compliant touch screen" if Device Manager does not list it under Human Interface Devices. The Wacom input driver indicates that although the system is unable to recognize the panel, it anticipated a pen/touch interface. Try a BIOS update or complete system reset; occasionally, the firmware disables the touchscreen. It's worthwhile to insist on assistance from a qualified technician because your laptop is still under warranty and is only eight months old. Others have experienced similar detection problems, so you're most certainly not alone.

RAM is a very common failure point in refurbished builds. Try: One stick at a time. Different slots. Known working RAM if available.

It is better to take the laptop back to the repair center and explain the issue. They might have missed reconnecting a cooling component. Sudden shutdown = thermal protection, and it can permanently damage your CPU/GPU if ignored.

Possible methods to solve your problem- Use a different cable You can restart everything Don not forget to check router settings Manually set IP for this Settings > Network > Ethernet then Configure IP > Manual Try a USB-C to Ethernet Adapter

Try opening it up only if you're experienced. Otherwise, it may be best to get it checked by a technician. The possible reason can be- A dead power brick (Slim). A faulty power supply (Fat). Or a damaged motherboard. These are some of the common factors if a PS is not starting or turning on.

The shortest thing that can work for you is Try Fn + Spacebar first. If that doesn’t work, update drivers or check BIOS.

If your Lenovo Z50 still shows a black screen after replacing both the screen and motherboard, but the power light turns on, the issue could be: RAM Issue: Faulty or improperly seated RAM can prevent display. Try reseating or replacing the RAM. BIOS Corruption: A corrupted BIOS may cause no display. Try resetting BIOS (remove the CMOS battery for a few minutes). Display Cable: Check the internal display cable connection between motherboard and screen. A loose or damaged cable can cause a black screen. Graphics Chip Failure: If the GPU is faulty (even on a new motherboard), no display will appear. External Monitor Test: Connect to an external monitor. If it works, the issue may be with the screen or connection. Try these things one by one and see what works for you.

Your Wi-Fi adapter may be disabled or malfunctioning. Try restarting your device, checking Device Manager (on Windows) or Network settings (on Mac), and ensuring the Wi-Fi driver is enabled and up to date.

You do not need to remove the glass to replace the display frame rubber (also called the LCD bezel gasket or cushion seal) on the MacBook Pro A1502 models (2013–2015).