As said Amigaharry2, check if Open firmware visible with other cards, or try to boot from installation CD.
Maybe your 9250PCI is 64MB version and your new resolutions is simply too large...
If Open firmware is visible, try to boot to MorphOS bootmenu:
- press "shift" during boot process
- od add parameter "bm" to your boot command
in bootmenu press "v" to toggle resolution
Nice commands but Open Firmware is not visible.
All my Radeon are 128 MB while Voodoo can manage 1080p 24bit with 16 MB only. Only the ATI 9250 PCI has 128 bit of memory bus and can still boot from PC. Maybe my Pegasos 1 does not support that card or is witched. The mark of Articia S.[ Edited by Goodman 27.04.2021 - 12:41 ]