![What are these 2 black slots on the back of the laptop called and what is it used for? Laptop is HP ProBook 645 G4. : r/whatisthisthing What are these 2 black slots on the back of the laptop called and what is it used for? Laptop is HP ProBook 645 G4. : r/whatisthisthing](https://preview.redd.it/qty0g197dh371.jpg?auto=webp&s=e0c222f5d1d3eac653bf0a5f8b3d4cc1fa931d48)
What are these 2 black slots on the back of the laptop called and what is it used for? Laptop is HP ProBook 645 G4. : r/whatisthisthing
Bigman Computers Ltd - *Refurbished HP ProBook 645 G4: RYZEN 5 Pro -2500U AMD Processor (2.0GHz upto 3.6GHz), 8GB RAM ddr4, RADEON VEGA 8 Dedicated Graphics, 256GB SSD (Solid State Drive), 14''
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HP ProBook 645 G4 - Smart Buy - 14″ - Ryzen 3 2300U - 4 GB RAM - 500 GB HDD - Notebook | Enterprise, Government, and Educational Technology
![Refurbished: HP ProBook 645 G4 Notebook, 14" FHD Display, AMD Ryzen 7 2700U Upto 3.8GHz, 16GB RAM, 512GB NVMe SSD, Vega 10, VGA, HDMI, DisplayPort via USB-C, Card Reader, Wi-Fi, Bluetooth, Windows Refurbished: HP ProBook 645 G4 Notebook, 14" FHD Display, AMD Ryzen 7 2700U Upto 3.8GHz, 16GB RAM, 512GB NVMe SSD, Vega 10, VGA, HDMI, DisplayPort via USB-C, Card Reader, Wi-Fi, Bluetooth, Windows](https://c1.neweggimages.com/ProductImage/AA0SD2005264A5V1.jpg)
Refurbished: HP ProBook 645 G4 Notebook, 14" FHD Display, AMD Ryzen 7 2700U Upto 3.8GHz, 16GB RAM, 512GB NVMe SSD, Vega 10, VGA, HDMI, DisplayPort via USB-C, Card Reader, Wi-Fi, Bluetooth, Windows
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For Hp 645 G4 Laptop Motherboard L12802-001 6050a2930301-mb-a01 Hsn-i15c R7-2700u Cpu - Laptop Motherboard - AliExpress
![HP ProBook 645 G4 14" Notebook - Ryzen 5 PRO 2500U - 8 GB RAM - 256 GB SSD - Natural Silver - Windows 10 Pro - AMD Radeon Vega Graphics - 10.25 Hour Battery Run Time 7AH92USABA 193905149773 HP ProBook 645 G4 14" Notebook - Ryzen 5 PRO 2500U - 8 GB RAM - 256 GB SSD - Natural Silver - Windows 10 Pro - AMD Radeon Vega Graphics - 10.25 Hour Battery Run Time 7AH92USABA 193905149773](https://www.compsource.com/mscs_images/epics/large/1059262314.jpg)