ASUS PCE-AC88 DualBand AC3100 PCIe WiFi Adapter
MU-MIMO 4T4R (4x4:4), 4 x RP-SMA Antenna
DualBand AC3100 (2.4GHz@1000Mbps + 5GHz@2167Mbps)
Broadcom BCM4366 Radio
This is it, currently the most powerful wireless performance throughput I've ever tested --> hitting LANPort max speed ~9xxMbps 
Product Photo
Information & reference :
- Product Information (ASUS Malaysia)
- Driver Download (both Windows & Mac)
- WikiDevi Information
- .
Straight to the point : Finally, the arrival of an unique 4 high-powered antenna Dual-Band AC3100 PCI-e wireless adapter to unleash AC routers potential 
I was trying to install on my DIY PC with Gigabyte GA-Z77M-D3H motherboard, however somehow one of the on-board connector is blocking due to the PCE-AC88's really big heatsink 
So eventually I installed it on another old DIY PC with ASUS H61M-K motherboard for testing purpose :
Wireless Performance Test :
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