ati 5770

I have an old ATi 5770 card which was reflashed to work in a Mac Pro 1.1 - I briefly tried it in a hack but it does not display correctly (colours askew, lack of available resolutions). Should this card now be reflashed again in order to use in a hack?

goldeng's Haswell CustoMac Mini Deluxe (mini-ITX) Gigabyte GA-H97N-WiFi | i7-4790 | ATI Radeon 5770 Multiboot El Capitan/macOS Sierra & Windows 7 Components Gigabyte GA-H97N-WiFi Motherboard: Newegg | Amazon Hackintosh compatible WiFi card for replacing the Intel® one that comes with the...