> putting M9 Radeon (9200 class) onboard was [...] faster solution on SAM440

Faster than the SM502 on the Sam460ex, but not faster than a PCIe graphics card.

> No W3D gfx card is avail as PCI-E, and out of all supported I believe only
> ATI Radeon X800 XT and some high end 9800 models are.

Radeon 9800 is not available as PCIe, and for the Radeon X800, the official Hardware Compatibility page lists no more than just the AGP-only R420 as the specific GPU supported.

http://en.wikipedia.org/wiki/ATi_Radeon_R400_Series
http://en.wikipedia.org/wiki/List_of_AMD_graphics_processing_units#Radeon_R400_Series

Regarding Warp3D:
https://morph.zone/modules/newbb_plus/viewtopic.php?forum=11&topic_id=9544&start=64

Regarding PCIe graphics card support for Sam460:
https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=9876&forum=11&start=26
https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=9876&forum=11&start=36