I upgraded my CPU and now my graphics cars isn't being detected

[callum.d.hind]

I upgraded my CPU from a Pentium G4400 and now my PC can't detect my graphics card.

https://gyazo.com/fa8b2fd2e635baf885a93668a8ce6ea7

I have a Radeon RX 460


Specs:

Computer Information:
Manufacturer: Gigabyte Technology Co., Ltd.
Model: G1.SNIPER B7
Form Factor: Desktop
No Touch Input Detected

Processor Information:
CPU Vendor: GenuineIntel
CPU Brand: Intel(R) Pentium(R) CPU G4560 @ 3.50GHz
CPU Family: 0x6
CPU Model: 0x9e
CPU Stepping: 0x9
CPU Type: 0x0
Speed: 3504 Mhz
2 logical processors
1 physical processors
HyperThreading: Supported
FCMOV: Supported
SSE2: Supported
SSE3: Supported
SSSE3: Supported
SSE4a: Unsupported
SSE41: Supported
SSE42: Supported
AES: Supported
AVX: Unsupported
CMPXCHG16B: Supported
LAHF/SAHF: Supported
PrefetchW: Supported

Operating System Version:
Windows 7 (64 bit)
NTFS: Supported
Crypto Provider Codes: Supported 311 0x0 0x0 0x0

Video Card:
Driver Not Detected
DirectX Driver Name: vga.dll
Driver Version Not Detected
DirectX Driver Version: 6.1.7600.16385
Driver Date Not Detected
OpenGL Version: 1.1
DirectX Card Not Detected
VendorID: 0x0
DeviceID: 0x0
Revision Not Detected
Number of Monitors: 1
Number of Logical Video Cards: 1
No SLI or Crossfire Detected
Primary Display Resolution: 1920 x 1080
Desktop Resolution: 1920 x 1080
Primary Display Size: 12.60" x 9.45" (15.75" diag)
32.0cm x 24.0cm (40.0cm diag)
Primary Bus Type Not Detected
Primary VRAM Not Detected
Supported MSAA Modes Not Detected

Sound card:
Audio device: Realtek Digital Output (Realtek

Memory:
RAM: 16343 Mb

Miscellaneous:
UI Language: English
Media Type: DVD
Total Hard Disk Space Available: 953766 Mb
Largest Free Hard Disk Block: 271335 Mb
OS Install Date: Dec 31 1969
Game Controller: None detected
VR Headset: None detected

 

[vapour]

power off, turn off psu 'O-' switch.
> unplug gpu
> turn on psu and boot
> power off, turn off psu 'O-' switch.
> unplug all cables and put gpu back, plug in all cables, boot
> Enter BIOS and switch graphics to GPU.