grub2 boot slowed down after catalyst install attempt

On 12.2, I had good boot time ( 20 sec for a spinning drive). Then I attempted to install catalyst 12.6 legacy driver which did not work. So I uninstalled it. However, since then the boot time increased by 10 secs. I ran mkinitrd again, re-installed grub2 but the boot still takes longer. I even re-installed all of mesa and the xorg stuff by force.

I notice the slowdown is particularly at the finish when it loads KDM. Where should I look for trouble ?