• Yokemate of Keyboards
    Yokemate of Keyboards
    Andreas_Wolf
    Posts: 12058 from 2003/5/22
    From: Germany
    > To my knowledge, MorphOS2.x can still only use up to 128mb of VRAM

    According to pega-1, MorphOS can use 256 MiB VRAM as long as the gfx card maps it as a linear 256 MiB aperture instead of mapping it as two physically separated 128 MiB apertures:

    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=7135&forum=11&start=48

    And in fact, apart from R300 based cards there are also Radeon 9250 cards with linear 256 MiB aperture mapping:

    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=7135&forum=11&start=64

    On OS4, which has the same limitation as MorphOS in this regard (i.e. only supporting one aperture), such cards can be used with their full 256 MiB VRAM:

    https://morph.zone/modules/newbb_plus/viewtopic.php?topic_id=7135&forum=11&start=67

    So I think it should work with MorphOS as well, although I've never read of anyone who actually uses a Radeon 9250 with linear 256 MiB VRAM aperture with MorphOS. General problem is that you can't see how many apertures the card uses from just looking at the physical card so it's hard to know before actually testing the card.

    > there was some discussion about some programmer trying to take
    > advantage of extra VRAM in some way

    Yes, pega-1 said he might put efforts into mapping the full VRAM range for usage from within MorphOS at some point in the future (see my first link) so that MorphOS can see the full 256 MiB VRAM range on cards with two physically separated 128 MiB apertures.

    > I don't know if that idea was ever turned into a project and completed, or not.

    I'm not aware of any new information since what pega-1 said over a year ago on that matter.
  • »25.08.11 - 09:59
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