Hi SpeedyV - Thanks for the response on this. Oddly thought id checked this thread more recently than this and not spotted your reply.
As I didn't spot your thread I went and got that usb2 Startech and found it didn't work at that resolution your just get a bunch of trippy lines! Ill sling that on ebay when I get chance.
Like you I have a 3080TI FE however I use all 4 displays off it. I've considered putting in a spare WX4100 that I have kicking around but its overkill, will ruin the look of my case and lead to routing wires outside the case.
Ideally I want to use the spare USB2 headers I have on the motherboard but ill consider sacrificing a USB3 one if someone can confirm it will do the 1920x480 resolution
Thanks