This message was posted on behalf of Intel Corporation
Based on the message it seems to be the driver 10.18.10.4242 is newer and in this case better than 10.18.14.4214, but that is something that only Toshiba directly will be able to confirm, and since the laptop detects that a newer driver is already installed as you mentioned it will not install an older driver.
In order to try to fix the problem, you can get into device manager, then look for “display adapters”, right click on Intel graphics and choose “uninstall”, and then try to install version 4214, you should be able to install that version that way.
If the driver version 4214 is showing as the latest driver version for your laptop then it will be better to keep that version.
Sometimes Windows does automatic driver updates, so try to install version 4214, then once you do that, if the problem gets fixed, you can try to disable the automatic updates since the driver version 4242 probably gets installed because of that.
Not sure if you are using Windows® 10, but if you are using it, here is the link to disable driver updates:
Since the problem happened after the BIOS update, one of the things to try is also to go back to the previous version, the BIOS updates most of the times are done to fix problems, but in this case going back to the previous version that was working before is an option as well.
Another thing we can try is to reset the laptop, not sure if you are using Windows® 10, but if you are using it, just enter “recovery options” on the search bar, then choose “Reset this PC” and choose “keep my files” to avoid losing any information.
After trying the steps above, if the problem remains, for this type of scenarios when you are using a laptop, we always recommend to get in contact with the manufacturer of it, in this case Toshiba, in order to get further assistance and a possible resolution for this problem, since they build it they are familiar with the software and hardware of it.
Toshiba’s phone number: 1 800-457-7777
Toshiba’s support site: http://support.toshiba.com/
Any further questions, please let me know.