Question Changed graphics card now PC won't boot

[harpin.zan]

Just to start off with some specs:

CPU: Intel - Core i5-8600 3.1GHz 6-Core Processor
Motherboard: Gigabyte - B360 AORUS GAMING 3 ATX LGA1151 Motherboard
Memory: Team - Vulcan 16GB (2 x 8GB) DDR4-2400 Memory
Video Card: GeForce GTX 1060 3GB ----> Now wanting to change to AMD Radeon RX580 8GB
Case: Deepcool - TESSERACT SW ATX Mid Tower Case
Power Supply: EVGA - SuperNOVA GQ 650W 80+ Gold Certified Fully-Modular ATX Power Supply

I decided to change my Nvidia 1060 to a Radeon RX 580. I followed the instructions on how to do a clean installation of a new graphics card (downloaded DDU, ran it in safe mode, uninstalled Nvidia drivers and again with AMD drivers), however I simply cannot seem to get the PC to boot with either my new or old GPU. My thought is that I somehow damaged the GPU partition of the motherboard when wiring up the new card. The GPU has 14 slots (6 slot and 8 slot) for the PSU, my old graphics card only had 6 slots so I wasn't sure how it should be wired up (and I couldn't find any instructions telling me the right way). Here's a rundown of what I tried:

1. Inserted the Radeon GPU with only the 6 slot connected to the VGA port of PSU. Computer went through multiple automatic reboots, but never managed to reach the BIOS.
2. In addition to the 6 slot connection, I Connected the 8 slot GPU to the second VGA port of the PSU (using a separate power cable). PC managed to boot, I got to the windows log-in screen, however it froze before I could do anything further. After that, PC failed to boot to BIOS on subsequent attempts.
3. Connected the 6 slot and 8 slot to one VGA port, no boot.
4. Connected just the 8 slot to one VGA port, no boot.
5. Connected the 6 slot to 2 VGA ports, no boot.

I've tried plugging in my old graphics card, and still no boot. The PC runs when I have no graphics card installed and the HDMI plugged into the motherboard. And of course I can't install graphics drivers while the GPU isn't plugged in. Help greatly appreciated.

edit: changed wording to make some parts clearer

 

[stefanos50]

As i see your motherbord have 3 pci-e x16 3.0 slots. Did you try another one?

 

[harpin.zan]

As i see your motherbord have 3 pci-e x16 3.0 slots. Did you try another one?

Not yet, I'll give that a go. Do I need to change anything in the BIOS settings if I'm going to do that?

 

[hang-the-9]

The manual and quick start that came with the video card would have had the instructions on how to hook it up. Always hook up all the power connections to the video card, so you will need both power connections to the video card, and make sure you are using the PCIe cables and that they are in the correct slots in the power supply if yours is a modular one.

If the system has no video with either card now you can try to reset the BIOS and motherboard. First go into the BIOS and note the drive settings it's on, AHCI, Secure boot on/off, UEFI boot, etc... Then unplug the system, take out the CMOS battery, hold in the power button for about 15 seconds. Plug in battery and wall power and see if it boots. You may need to set the time and if you get a "no bootable device found" error, go into the BIOS and check those drive settings, they may need to be set again to what they were.

 

[harpin.zan]

OK so I managed to fix my issues, it was a simple dumb mistake on my end. When I went into the BIOS I had forgotten that I switched the initial graphics settings to integrated when I was switching cards, somehow thinking that I had to do that before I installed the new drivers. I just had to switch the initial graphics back to the PCI slot with the graphics card inserted, and now it works as intended. Thanks for your help anyway .

The manual and quick start that came with the video card would have had the instructions on how to hook it up. Always hook up all the power connections to the video card, so you will need both power connections to the video card, and make sure you are using the PCIe cables and that they are in the correct slots in the power supply if yours is a modular one.

Hmm I looked at the online manual for the radeon RX 580 before and all it says is that you should "connect any supplementary PCI's 6/8 pin power connector", nothing about how it should be wired up to your PSU specifically. At least I know how to wire it up now.