are there any PCIe wi-fi adapters with 5Ghz capabilities that are whitelisted and will work with El Capitan?
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Mobo: manufacturer/model + bootloader(Clover/Chameleon/Chimera)
CPU: detailed CPU model + motherboard chipset
Graphics: all graphics devices + laptop internal screen resolution
For example, typical Ivy laptop:
Mobo: HP ProBook 4540s (Clover)
CPU: i5-3320m/HM76
Graphics: HD4000, 1366x768
Use CPU-Z on Windows to find CPU (Core iX-xxx) and motherboard chipset (HMxx), and graphics capabilities. For a laptop, these details are important and affect critical installation procedures.
Note: When specifying your bootloader, if using Clover legacy, please be sure to specify "Clover legacy"). Specifying "Clover" will be assumed as "Clover UEFI"