@keropi
You say that your G-Rex has only one PCI slot with proper DMA, do the other PCI slots have DMA between each other.
With the Mediator there is no DMA between PCI and system RAM due to limitations with the A1200 expansion slot. Elbox get around this by using TV-card drivers that access the graphics cards RAM using full PCI-PCI DMA.
I'm not sure if the G-Rex TV-card drivers work the same way as Elbox ones though.
