Umm ... there are tons of pci-e adapters that work for Windows 8/8.1 and not that expensive at all ... you have to look around. I bought this one for $40 and its a wireless ac adapter (better then n) and yes only $40 and it works on the Win 8.1 desktop just fine.
Also has built-in Bluetooth 4.0 so I can copy files to & from my android device (pictures, music, etc) without need for cables. Pretty functional card. Uses intel chipset as well. Impressed at quality & price.
Gigabyte GC-WB867D-I
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