Grey Screen with Cursor on Boot (RX570)

[Pericles]

I've been trying to boot MacOS Mojave (10.14.4) after installation on a system I've built.

 

I was able to successfully install Mojave through my USB, it seemed like the installer recognised my gpu and was working with it in the installation screen as it looked like it was outputting video at 4k resolution. When the computer restarted I then booted into the "Preboot" option on clover twice (the first time I tried the progress bar got to a certain point and then the system restarted) and on the second attempt the progress bar filled up completelly and the mac installer counted down to a restart (which I took as meaning that it had successfully finished the installer). After restarting however I tried to boot into MacOS from the SSD I installed it on, the apple logo showed up with a progress bar that filled up completelly before the screen turned black, then grey with a cursor over the grey screen. Also, it's probably worth noting that the GPU's fans continue to spin from turning the system on, up to the point where the screen turns grey after which they stop spinning.

 

My system specs are as follows:

CPU: i5 3470

GPU: RX 570

RAM: 16GB DDR3 1600MHz 

MB: Asrock B75m r2

SSD: Samsung 850 Evo 250gb

WiFi/BT: Fenvi FV-T919 PCIE Card

 

I am thinking that it's probably a gpu related issue as everything about the installation process has gone pretty smoothly up to the point where it's displaying a grey screen at bootup (and not going further). I have attached a photo of the output from rebooting with the verbose bootflag (it's missing one line at the bottom "busy timeout[1], (240s): 'AppleACPICPU'"), after the verbose output stays on the screen for a few minutes the screen then turns grey with the cursor and hangs there.