High Sierra to Mojave issue - Now won't boot

[sappdb]

Hoping I didn't brick my desktop build. Here are the steps I took.

I had a clean working High Sierra build last year. I moved and have been using my Macbook Pro since. I finally got around to setting up the hackintosh again a couple of days ago, well after Mojave was introduced. Apparently Nvidia is way behind on updating the drivers and I didn't notice this until after updating from the App Store (I knew better). Just in case, I made a fresh Unibeast bootable USB.

It seemed to hang up a couple of times while updating from the App Store, but eventually it booted into Mojave after restarting a few times. I updated with the newest Multibeast and most everything seemed alright - WiFi worked, audio worked, etc. But, there were obvious graphics and booting issues, as well as every time I opened the App Store, the computer froze. Sometimes it would randomly restart. Graphics were manageable, but the bootloading screen looked like a few random bars of static and then would boot into Mojave without any options or ability to enter BIOS or boot from USB (that I could tell). Also, Chrome showed many hover "static" backgrounds and the URL dropdown was illegible "static". I followed this guide to fix the lack of current Nvidia drivers, which worked after rebooting. I also followed this guide to fix the Chrome issues, which seemed to only work very temporarily.

I wasn't happy with this build as it had many distracting flaws so I decided I would try to boot from USB somehow and start fresh. I should have used Disk Utility while in Mojave to wipe the SSD, but instead decided to remove the CMOS battery to reset the BIOS in hopes that I would be able to boot from USB to do a clean install. Now it won't boot at all, won't display anything, won't boot in safe/verbose mode via keyboard at POST, and I have no way to report on the issue in more detail or start fresh.

Any help would be appreciated. This isn't my first time installing fresh or upgrading, so I'm at a bit of a loss for what to do next.

 

[sappdb]

I fixed it. In case anybody comes across a similarly "bricked" machine, the solution I was able to implement involved resetting the BIOS. In order to do this, I "reseated" all the major hardware components (excluding the fans and USB ports) by unplugging them and their connectors to the motherboard. Then I removed the CMOS battery for a few minutes. In order to reset the BIOS, the power supply and RAM needed to be plugged in. Once this was done, I was able to reach the bootloader screen. Further plugging in the graphics and WiFi cards allowed me to reach my previous install with no problem.

Although the installation guides mention users with my type of graphics card should stay on High Sierra, the above mentioned fixes work ok, with minor display issues. I'll probably revert back to High Sierra until the supported Nvidia drivers are released.