Check WiFi card detection and BIOS settings:

Bash
# Check if WiFi hardware is detected
lspci | grep -i wireless
iwconfig
rfkill list

# Check current driver status
lsmod | grep -E "(iwl|ath|rtl|bcm)"
dmesg | grep -i wifi | tail -20

1. Hardware Detection Phase

• Verify WiFi card in BIOS (ensure not disabled)
• Check hardware switches (physical WiFi toggle)
• Run lspci to confirm card detection
• Check rfkill for soft/hard blocks

2. BIOS Configuration

• Enter BIOS/UEFI (usually F2, F12, or Del during boot)
• Navigate to Advanced/Integrated Peripherals
• Ensure WLAN/WiFi is "Enabled"
• Check Secure Boot status (may block unsigned drivers)
• Save and exit

3. Driver Resolution

• Identify exact WiFi chipset model
• Install appropriate firmware package
• Blacklist conflicting drivers if needed
• Restart network services

4. Network Stack Recovery

• Reset network configuration
• Restart NetworkManager/systemd-networkd
• Test connectivity

Example 1: Intel WiFi Card Not Detected Input: lspci shows no wireless device, BIOS shows WiFi enabled

Bash
# Check BIOS settings first, then:
sudo modprobe iwlwifi
sudo apt install firmware-iwlwifi  # Debian/Ubuntu
# or
sudo pacman -S linux-firmware     # Arch

Example 2: Realtek Driver Conflict Input: WiFi connects but drops frequently

Bash
# Blacklist problematic driver
echo "blacklist rtl8xxxu" | sudo tee -a /etc/modprobe.d/blacklist.conf
# Install proper driver
sudo apt install rtl8821ce-dkms
sudo modboot
reboot

Example 3: Hard RF Block Input: rfkill list shows hard blocked WiFi

Bash
# Check physical switch, then BIOS
# In BIOS: Advanced → Network → WLAN Auto Disable: Disabled
# Save and exit BIOS