/* AGP aperture is disabled */
        if (agp_bot == agp_top) {
-               logical_addr_low  = adev->gmc.vram_start >> 18;
+               logical_addr_low = adev->gmc.fb_start >> 18;
                if (adev->apu_flags & AMD_APU_IS_RAVEN2)
                        /*
                         * Raven2 has a HW issue that it is unable to use the vram which
                         */
                        logical_addr_high = (adev->gmc.fb_end >> 18) + 0x1;
                else
-                       logical_addr_high = adev->gmc.vram_end >> 18;
+                       logical_addr_high = adev->gmc.fb_end >> 18;
        } else {
-               logical_addr_low  = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
+               logical_addr_low = min(adev->gmc.fb_start, adev->gmc.agp_start) >> 18;
                if (adev->apu_flags & AMD_APU_IS_RAVEN2)
                        /*
                         * Raven2 has a HW issue that it is unable to use the vram which