What might be wrong now?

I think there is not enough vmem on GPU1. Monitor connected to GPU1? If so you need an integrated card or replace 1st GPU by 6 or 8Gb card.
Yes, monitor is connected to GPU1... so I have to disconnect monitor from GPU1 to try fixing this issue?

Is there a way with a command line to disable GPU1 mining on Phoenixminer?
This mobo just have a DVI conector for monitor but I dont have a DVI monitor

it doesnt have HDMI Video conector integrated

neither i have a 6 o 8GB GPU

Even if you're disconnect your monitor Windows will always take some videomemory from 1st GPU. Only way is integrated videocard or card with 6 or 8Gb. Or mine other algo on 1st GPU.