Comment by NikkiA
9 days ago
And that unusuability was mostly due to the driver model change, once native Vista drivers appeared it performed better than XP/XP64 unless you were running old video hardware that couldn't handle aero - in which case you were still better off running Vista with the classic UI, although that did entail forgoing the Luna styling.
Even with native WDDM drivers it performed poorly in desktop graphics, because Vista also removed all GDI hardware acceleration support. This caused many 2D graphics operations to execute in software, or worse, an even slower mix of hardware and software rendering. Windows 7 improved on this by re-adding hardware acceleration for some GDI primitives and adding aperture windows to reduce DWM memory footprint.