I would love to be able to however that requires having the hardware however I can guide you guys on how to patch the info.plist on the fly at boot up time and keep your kexts in S/L/E vanilla and live through an update with out having to reinstall any modified older versions of some kext you have on your desktop. The only thing this will depend on is apple not removing the Baffin line from the kext like they did in one previous update however we can still fool macOS by patching multiples at a time expecting them to move it else where.
To do so all we need is the deviceIDs and VendorID for that given card which is easily acquired via DPCIManger which is available
here. Then we open our efi/clover/config.plist with clover configurator which is available
here and click on the kernel and kext patches in the left hand pane. In the window hit the + sign under the kext to patch box and add these entries to to it for yours Gigamaxx and anyone else who uses the same deviceIDs and VendorIDs as you do.
Name
AMDRadeonX4100
Find
67E01002
Replace
67DF1002
Then tick the info.plist patch box on the right.
I like to tick the debug box above the kext to patch box to see the patching at boot up in verbose to see if it did patch it or not. Although this isn't needed but i like to do it until i got it how I like it.
Then make sure you have your FakeID in the devices section 0x67EF1002
Then it looks like you need to inject ATI so on the graphics section tick injectATI and it should work with the native vanilla AMDRadeonX4100.kext
To test make these changes and change your AMDRadeonX4100.kext/Contents/info.plist back to it original.
Then you won't have this kind of problem.
For others with a similar GPU using the Baffin card but maybe have different DeviceIDs simply gather that info from DPCIManger and change the replace value in Kexts to patch section
Hope this help and keeps your systems up to date without the break
Happy Hacking
Carpentry
