Please give the next level of detail in "Testing older video cards may require
creating
and editing xorg.conf, or moving the DRI drivers for those cards out of the way to force
fallback to llvmpipe." Two explicit examples, or pointers to tools, would be nice.
I have Radeon 9250 Pro [RV280] which today gets fallback mode on Pentium 4 with sse2.
My skills with xorg.conf are rusty [see how successful "no xorg.conf" has
been!],
and "moving drivers out of the way" is nebulous.
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