I am trying to get dual screens running on my X5000 running a Radeon X1950.

Anyone else having luck with this?

It can be my specific setup where I have HDMI screen via an DVI adapter on my main screen and a DVI to VGA adapter on my second screen and larger screen. Old trusted Iiyama screen.

I can get the two screens to show the X5000 bootlogo on both screens. But when MorphOS (3.18) start the second screen is black except some lines in the left side. My primary switches off after a few seconds.

I can see here https://library.morph.zone/Multi-display that there is limited support on anythin else but PowerMac so I was just wondering if anybody else have had success before I tinker anymore.

DVI to VGA means you are using an analog signal which is AFAIK not supported for DualHead (outside the iMac where it is the only option).

"Old trusted Iiyama screen" sounds early LCD or even CRT which may not support DDC (mode recognition), better try with 2 proper digital screens.
And by "proper" I mean proper as I have a ca 2002 18" Phillips that has a DVI input only accepting VGA signals...

I have an X1950 and the cheap DVI-HDMI adapter didn't work with the second screen. With DVI cables it works without any problems (I have monitors with DVI connectors).

DVI-HDMI adapters will generally fail if your monitor is >1080p. VGA adapters will definitely fail.

Yes, it is clearly better to avoid the adapter here:)

Thank you very much! Will drop the VGA adapter (as a min.) and see where it goes.