I was then asked if it was possible to show the Keynote on an iPad at the same time as the Keynote as the speaker couldn’t see the presentation on the wall behind him. Time spent on Google (where else!) bought up several suggestions, the most promising of these looked to be Air Display, the Mac host was free and the App for the iPad was £12.99.
I installed it here first on a similar MacPro and 2 monitor setup, it worked perfectly with virtually no ‘lag’. So off to the Chapel to try it out there, I installed the Mac Host and that was it - everything just went blank on a restart!
I tried several restarts including holding the shift key, nothing worked so I bundled it in the car to take home and troubleshoot.
My first thought was the ‘hacked’ 3Gb graphics card, it had originally been a PC card but had Mac Firmware installed, I’d bought it on eBay and had around 3 years of perfect use from it, I only had a 1Gb Mac GFX card so put that in - then the Mac complained it couldn’t run Mojave as a ‘Metal’ GFX card was needed - it was a vicious circle!
The only solution I had was to do a clean install of High Sierra using the 1 Gb GFX card then hopefully update to Mojave by installing the 3Gb card. In the meantime I needed something for the next Sunday service, I spent around 4 hours looking on the web for something suitable, I had it in mind to buy a late Mac Mini (I’m not a laptop guy, my main Mac is a 2020 5K iMac and I like my large screens!).
I eventually found a 2018 Mac Mini with 128Gb Flash storage and 32Gb RAM for £580 at Music Magpie with guaranteed next day delivery. I didn’t need huge storage, the RAM was more important to me, I could always add a USB3 stick for more storage.
The Mac Mini arrived as promised the next day, plugged a keyboard and mouse in and an HDMI monitor and started it up, it sprung into life as quick as I expected, I downloaded Keynote and also Air Display, installed and tested it, it all worked perfectly so I’m all set for next Sundays service.