Having similiar issues with the same error, also on an MSI laptop with a dedicated graphics card (1070). The difference for me is that Solus will boot off the hard drive afterward. Initially, trying to install anything, including updates, causes the system to become unresponsive, though the mouse cursor would still move. This occurred most recently while using DoFlicky to install the current Nvidia driver, though running the software updater did the same thing in past attempts.
The driver and bbswitch seemed to install successfully (the system had locked, but afterward eopkg told me it was installed), but now the desktop will no longer display and I can only get to the command line via ctrl+alt+F1. I ran a system update from there (and also tried to install the nvidia driver and bbswitch again, this is when I was told it was already installed), but it didn't change anything. I also tried the nomodeset thing from the link posted by kyrios but it has no effect. Additionally, pressing spacebar repeatedly, both before and after entering the LUKS password, doesn't seem to work.
FWIW, Linux Mint gives me similar issues on this particular laptop, however Manjaro will install just fine. Different USB devices and ports have been used as well, for both Mint and Solus, with no effect.
Manjaro is cool and all, but... I like Solus better. I'm happy to provide anything I can to help solve this issue for the both of us.
