I upgraded from ATI Radeon HD 5670 256MB VRAM (or whatsoever) to ATI Radeon HD 6450 2GB VRAM. When I was booting my PC it seemed quite slow. I began to panic when I saw 256 MB in PCI devices listed in 'hardinfo'.
Just go to the CCSM (Config Compiz Settings Manager) OpenGL-> Uncheck "Sych with VBlank"
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2 years ago